Poor plant growth for a number of species, advise requested

[Lycolus]

Hello everyone!

I have been lurking on a number of different aquarium forums for some time, but as I continue to have less than desirable results for my tank I have finally decided to make an account here. Hopefully, the combined knowledge of all the smart people here will be able to push my tank in the right direction because frankly, I am feeling a bit worn out from my 'fight' in getting this tank to a nice stable condition. I have not given up hope yet, but something needs to change.

Okay, first some context. I started out with this hobby some 7 years ago I think, at the time I had a smaller tank of about 60* 30 * 40 cm. I had some smaller issues, but at the time, some plants growing too well was the largest issue I faced 😉. I kept that tank for a year or two and then decided that I would like to have some more room to play around with, as I figured out that I really liked to keep plants in the aquarium and that fish are more of a supporting element for me. So I upgraded to the tank I still have today, a 100 * 45 * 40 cm tank. Even though I have gone through multiple complete teardowns and re-designs since, I have never been able to get this tank nicely balanced for an extended period of time. Such a redesign of the tank usually happened at the point that I thought that there was no coming back from the current situation. Of course, trying the exact same thing again will likely result in the same outcome, so I did seek out local fish shops and help online in order to try and get my tank 'just right', which resulted in changes in lighting, filtration, substrate and fertilisers over the iterations. As you might have guessed however, I am not quite there yet.

So on to my current tank, first some details:
As I mentioned before, the current tank is 100 * 45 * 40 cm (I am assuming ~ 135 litre water).
The current setup is over a year old.
Filtration is done by a fluval 306
Lighting: 2 white 5050 SMD LED strips (60 leds / m, advertised as 1020 lumen per meter) and one RGB led strip that I use for coloration. These white strips are currently on for 8 hours a day at 50% output. Some months ago these were on 75% but I got algae issues so I decided to lower them. (I really wish par meters were cheaper so we could easily compare 'light intensity' between setups..) These strips are fixed to aluminium profiles which rest on the side of the tank, so a few centimetres above the water surface.
Substrate: Tropica aquarium soil.
CO2: No dosing (As a student I am really trying to keep cost down, so I'd rather not start CO2 dosing if possible)
Fertilizers: Two times per week NPK, two times per week micro. I started this specific dosing regime 5 weeks ago based on internet recommendations because I noticed holes forming in the older leaves which eventually completely broke down. I have the impression that the new dosing has significantly decreased this problem at least. The specific ratios I add: 1 ppm PO4, 10 ppm NO3, 15 ppm K per week (dry salts premixed, half on Monday, half on Thursday), and easy life profito for the micro side of things, a little higher than their recommended dose (15 ml, half on Tuesday, half on Friday). These numbers were advised by... a website that I can't remember at the moment...
Water changes: I change 50% of the water once per two weeks.
Fish: 15 Neon tetra's, 6 otocinclus (I would like to get some more) and one very shy Ancistrus.

On to the pictures of my tank.
Overview of the entire tank (sorry for the glare!)

Some closeups of plants that are not doing great:
Limnophilia: New growth looks nice and green, older growth (even close to the water surface) quickly turns brown (not the red tint you would expect from being close to the light if that is not clear from the image).

Lotus: Some of the new leaves are still getting dark spots / holes / deteriated edges, even though there also plenty of leaves which look fine

New growth on Rotala is also green (but I think rather small) and suffers from the same problems as Limnophilia with older leaves not lasting long.

Then, a plant that had been doing great until about a week ago, my Microsorum Pteropus Trident. About a week ago, I saw a grey / black spot on one of the leaves which seemed to spread (or they all suffered from the same unknown change in the aquarium) and almost completely obliterated the leaves on all the plants. I tried removing the affected leaves but it still spread /affected the other leaves as well. This is one of the few plants that seemed to be doing well before.

The plant I am trying to grow at the fron is the Marsilea Hirsuta. I knew beforehand that this plant was going to be a bit of an experiment but I am not sure what to do with it. On the one hand, the rough texture of the substrate makes it so that my Ancistrus regularly uproots these tiny plants. As you can also see the older leaves don't look great and BBA are starting to grow on/ near to these plants. However, I can also see plenty of new growth coming out from beneath the substrate. I have tried removing the worse looking parts, but I often uproot the new growth as well when doing so. Is there a future for this plant with my setup?

Finally, I would like to add a picture of some floaters I have, as perhaps some people experienced in the 'duckweed index' will be able to say something meaningful about my tank by looking at it, even though it is not duckweed 😉. I have also added a picture of my Echinodorus 'ocelot' as it has been getting extremely red new growth. I know coloration is also related to nutrients so perhaps someone is able to use this as some meaningful indication.


So that turned out to be quite a long read, thank you if you made it all the way here! As you can see from the images, plant health is far from optimal. I expect that the BBA and some minor other algae that I have been seeing are related to this fact. I also notice that I have a 'protein layer' (not sure what the correct english term is) on top of the surface. I tried to combat this with the custom spraybar that I made but I suspect the source of the problem is the leaves of the plants breaking down. I am currently working on getting a water report for my local tap water to see what elements are already in there.

As I mentioned at the start of my post, I have tried quite a number of things so far and I just can't seem to get consistent (even if slow) healthy growth. I am open to any suggestions people might have. If I missed anything that could help with giving advice, please feel free to ask and I will respond as quickly as possible.
Thanks for sharing your knowledge!
Cheers!

 

[Hufsa]

As you probably know, its not likely to be one single thing that is wrong with your tank, but likely a combination of things that can be improved to create an overall better balance.

Some thoughts;
Your lights are a little bit of a wildcard since they are homemade(?), but you say you got more algae at 75%, so you are now at 50%.
Have you tried going to like 30% just to see what will happen? If you notice the plant growth slowing too much / deteriorating nothing is stopping you from turning it back up again.

I used to have a lot of stunted unhappy plants and plenty of algae in my (low tech) tank, and had eventually tried almost everything except turning the light way down.
I turned it down all the way until I saw the plants begin to struggle, which means they werent getting enough light to meet their LCP (light compensation point).
Algae growth had almost disappeared at this light level but plant growth was very slow.
From there I gradually turned the light back up again a touch, to try to find a sweet spot.
I believe I am very close now to the sweet spot as algae is minimal and my plants are the happiest they have ever been.

Im starting to think balancing light vs available CO2 is the most critical part a low tech tank, and the "sweet spot" may be surprisingly small.
Old growth deteriorating rapidly supports the theory that your plants are growing faster than the CO2 supply can keep up with.
They are stripping their old leaves of carbon, trying to keep up with the growth the lighting level demands.
Algae loves unhappy plant leaves.

I think its very unlikely to be a lack of overall nutrients, your plants look nice and green, especially the floaters and the dosing you report should be plenty.
Your floaters are a bit curly leaved, I recently had the same issue and an increase in Magnesium seems to have fixed it. Do you dose any Mg and if so how much?
Do you have a TDS meter? Keep an eye on your TDS to check that you do not get too large a buildup of ferts, for the safety of your livestock.
Your plants are unlikely to consume all of it and I note you change water every two weeks instead of every week.
Which is perfectly okay, just needs a little bit of monitoring and possible adjustments 🙂

You should look to get rid of the protein film.
Your suffering plants are probably contributing a lot to it, this may be a vicious cycle as the protein film hinders gas exchange,
giving your plants even less CO2 than they already get, making them suffer more, and releasing more chemicals as they decay.
Make sure whatever skimmer solution you go for doesnt eat your critters, the Eheim Skim especially is notorious.
I personally like the cheapo SunSun ebay skimmer.

Try to maximise flow as much as you can, within the comfort zone of your livestock. Since you dont inject CO2, atmospheric gas exchange is your plants carbon source.
You dont need to fear too much surface agitation offgassing injected CO2.
A large area of surface exchange and good flow will deliver a small but steady supply of carbon to your plants.
Ideally you want to see some movement on all the plants. They dont need to be whipping in the current though.
If you want to squeeze more flow out of your setup, you can try to tape up a few of the holes of the spray bar with PVC tape, to see what effect it would give.
Many make custom spraybars optimized for their tank and filter setup.

Im sure if I have forgotten something I will remember it right after I press 'post'.
Hope its helpful and wish you better success with your tank

 

[John q]

Glad somebody mentioned the lights, I was beginning to sound like a stuck record. Lol.

Lots of good information above, the only thing I'll add is the echinodorus ozelot looks healthy to me and will put out red leaves, or at least mine does. The black spots on the microsorum trident could be lack of co2 related and also could be the cause of the melt, again had the same issues for the same reasons, but I've also had similar issues with this plant when I dosed my fertiliser directly above it, could be unrelated, just a random thought.

 

[Hufsa]

Trident seems to be a whiny widdle baby, I got melt on mine when I trimmed it last and it didn't stop melting until it felt like it was done. I think its one of the neediest common variants of Java fern. I think it will improve when the rest of the plant growth is improved.

 

[Andy Pierce]

At at guess, too much light and fertiliser for the amount of available CO2. You're at something like 1/3 to 1/2 full strength EI dry salts ferts which absent injected CO2 won't be consumable by your plants (EI dosing is supposed to be used up) and so will build up with time. Your once every two weeks 50% water change should be bumped up to weekly 50% water changes as would be EI standard. I've done a lot of Marsilea hirsuta and in my experience (Marsilea hirsuta | Fireplace aquarium), despite the claims of easy growth in low tech setups, this is a plant that needs at least moderately high light and injected CO2 to thrive. My suggestion is to get an injected CO2 setup. The outlay costs will be a couple hundred £, but once that's done you'll find the operating costs are actually very modest. If you're going to stick with low tech (no injected CO2) I would reduce both lights and ferts way down and go full-on low-tech.

 

[Hufsa]

Theres no need to reduce ferts, excess ferts dont cause algae, this is an old myth. Ive dosed full EI in a low tech tank (30-3-30) with no more algae than when I dosed very little. Reducing ferts would mean you could start running into nutrient deficiencies in addition to the other problems and will needlessly have to play whack-a-mole for every single deficiency, which takes a lot of knowledge and time and is pointless. Dose ferts in excess to the needs of the plants, and change some water. Only reason to reduce is if you for some reason can't do enough water changes (it happens), and need to reduce levels a bit to avoid buildup.

 

[Lycolus]

Wow thanks for all the quick responses so far! I really appreciate all the input I have been getting!
Let me try to respond to the points mentioned.

Snip

The light: For me, they have also been a bit of a wildcard, they are in fact not homemade (the brackets are though!) they are actually part of a specific aquarium set. This set is offered by a shop that specializes in led-lights though, not one focused on aquaria. They could not offer me any specific plant-growing specs at the time, but as I had seen plenty of people grow beautiful aquascapes under 'cheap amazon lights' I thought I would risk it. In hindsight, I have been unsure about the lights a number of times since (mostly whether not strong enough or actually too strong), so I am not quite sure I would make the same decision.

I actually did not realize that too much light could also force the plants to try and grow too fast and result in poor growth. My understanding was that the excess light was 'unused' but in this high-energy system algae would get a chance to overtake the aquarium as the plants are limited by other things than light. This is actually a very interesting angle to try, something I surely did not try before! Like I mentioned, I have been unsure about whether the lights are too strong are not strong enough for quite some time!
On a related note, would a red or blue light on a very low setting (like 10%) produce enough light to affect algae / plant growth? I thought about using the RGB strip the extend the viewing hours a little using 'sunrise' / 'sunset' / 'moonlight' like settings, but I don't want to add 'another parameter' at the moment if it will have a significant impact.

I do not dose any magnesium, what levels should I aim for? I think I might have a dry salt around here somewhere I could use for that.
I also do not have a TDS meter, even though I have seen some discussions on the topic. I might actually be interested in getting one (I admit I did not search myself before asking this one), is there any recommended brand /type I should keep an eye on? Are there large quality differences or will a 'simple' / 'cheap' one do just fine?

The current is already on the high side of things for my fish, but I am sure I can get more surface movement out of my current setup, I will try and fiddle around with it sometime tomorrow and try and look for some other methods to skim the top.

Lots of good information above, the only thing I'll add is the echinodorus ozelot looks healthy to me and will put out red leaves, or at least mine does. The black spots on the microsorum trident could be lack of co2 related and also could be the cause of the melt, again had the same issues for the same reasons, but I've also had similar issues with this plant when I dosed my fertiliser directly above it, could be unrelated, just a random thought.

Trident seems to be a whiny widdle baby, I got melt on mine when I trimmed it last and it didn't stop melting until it felt like it was done. I think its one of the neediest common variants of Java fern. I think it will improve when the rest of the plant growth is improved.

Glad to hear the ozelot looks good. Too bad I did not know this about the trident beforehand though, might have passed on it. I will try to keep an eye on where I dose the ferts next time.

Snip

Thanks for the suggestion Andy. I must admit, I have really been considering the CO2 setup just to have control over another variable in the setup. As soon as I have a stable income it is very likely I will switch over at some point, but there is also a silly part of me that really wants to "get a low-tech to work", as plenty of people have shown that it is possible. I do need to consider however that buying new plants and such is not free either and it might just be cheaper in the long run if I keep going like I did in the past. Let's just hope that the next time that I replant the entire aquarium, it is because I wanted to rescape, not because I 'had' to 🙄.

Theres no need to reduce ferts, excess ferts dont cause algae, this is an old myth. Ive dosed full EI in a low tech tank (30-3-30) with no more algae than when I dosed very little. Reducing ferts would mean you could start running into nutrient deficiencies in addition to the other problems and will needlessly have to play whack-a-mole for every single deficiency, which takes a lot of knowledge and time and is pointless. Dose ferts in excess to the needs of the plants, and change some water. Only reason to reduce is if you for some reason can't do enough water changes (it happens), and need to reduce levels a bit to avoid buildup.

This was my thought on the approach as well, dose in excess to make sure ferts are surely NOT the reason, then change the other parameters until I find the one that is 'unbalanced'. That is under the assumption ofcource that I do not reach a level of 'too much'. Do you recommend any changes in my current approach? (any ferts I am missing? Smaller dose? Bigger even?)

 

[Hufsa]

The light: they are in fact not homemade

Ah my bad, either way I think they will likely be perfectly good for growing plants, you just need to find the right intensity.

On a related note, would a red or blue light on a very low setting (like 10%) produce enough light to affect algae / plant growth? I thought about using the RGB strip the extend the viewing hours a little using 'sunrise' / 'sunset' / 'moonlight' like settings, but I don't want to add 'another parameter' at the moment if it will have a significant impact.

Generally you only want the lights on when its above the LCP of plants. Light below this will mainly just benefit algae. Try to also limit your ramping times to 30 minutes at each end.

You could shift your lighting period towards the end of the day if that fits with your schedule, although ambient light may wake up your plants earlier.
If you shift the lighting period your plants may need some time to reprogram their internal clocks, so dont fret if you see them "closing up for the night" too early at first.
Its not uncommon to be able to run low tech tanks with 10 hours of light, so I suspect if you are willing to wait a bit while you fix your plant growth, you can after that extend lighting period to see how much your tank can tolerate. But I would leave the hours as they are for now, less changes all at once.

I do not dose any magnesium, what levels should I aim for?

Lack of Mg manifests as a general paleness of the plants, both in old and new growth, which on further examination I do not see in your pictures.
So it would seem like your plants are getting sufficient Mg from your tapwater or some other source.
My curly floaters were also a bit pale, which would fit better with Mg. Its possible it was a coincidence or some other unknown cause, so you can probably disregard that bit of advice. It doesnt hurt to add a little bit at water changes anyway if you want though, you could add 5 ppm at water changes and/or do a little booster of 0.5 ppm with your macro dose.
This should be lowest priority and could be optional in your situation since everything seems quite green 🙂

I also do not have a TDS meter, ... is there any recommended brand /type I should keep an eye on? Are there large quality differences or will a 'simple' / 'cheap' one do just fine?

I would be interested in the answer to this as well, I got a really cheap one off Ebay and it -seems- to be fine to me, but I have no way to control it so would welcome others with more experience on the matter. I cant confidently suggest any particular one because of that. Although I think I remember seeing Hanna mentioned as a very respected brand.

The current is already on the high side of things for my fish, but I am sure I can get more surface movement out of my current setup.

If your fish dont want more current I would definitely respect that, after all, they are the ones who have to live there Surface movement is good though, and try to ensure the flow passes down to your carpet if you want to give it a fighting chance to succeed.
As a temporary measure against the film, paper towels work ok but are not nearly as efficient as a skimmer.

I must admit, I have really been considering the CO2 setup just to have control over another variable in the setup. As soon as I have a stable income it is very likely I will switch over at some point, but there is also a silly part of me that really wants to "get a low-tech to work", as plenty of people have shown that it is possible.

Sure, CO2 injection lets you turn things all the way up to 11 on the dial, it makes plant growth so much faster but it also makes things go wrong faster as well.
Ive never seen quite so spectacular algae blooms as in CO2 injected tanks where something has gone off balance and careened into disaster.
Its a lot like going from a tractor to a racecar. Sure it looks nice and it goes damn fast, but with the tractor you have a lot more time to react before you crash into that tree by the roadside. The requirements for maintenance and trimming of plants also increases quite a lot with injection, and low tech tanks tend to be more resistant to benign neglect.
Just some food for thought.

This was my thought on the approach as well, dose in excess to make sure ferts are surely NOT the reason, then change the other parameters until I find the one that is 'unbalanced'. That is under the assumption ofcource that I do not reach a level of 'too much'. Do you recommend any changes in my current approach? (any ferts I am missing? Smaller dose? Bigger even?)

I would stay with your current ferts as the growth on your plants look super good. Your red sword looks really gorgeous.
This is provided the TDS is kept at a stable range with your water change regime. If its ever-increasing then I would scale it down a bit, but not dramatically.
Once you have plants growing well for the most part you can play with ferts to your hearts content 😁

 

[N00BIE]

Hello everyone!

I have been lurking on a number of different aquarium forums for some time, but as I continue to have less than desirable results for my tank I have finally decided to make an account here. Hopefully, the combined knowledge of all the smart people here will be able to push my tank in the right direction because frankly, I am feeling a bit worn out from my 'fight' in getting this tank to a nice stable condition. I have not given up hope yet, but something needs to change.

Okay, first some context. I started out with this hobby some 7 years ago I think, at the time I had a smaller tank of about 60* 30 * 40 cm. I had some smaller issues, but at the time, some plants growing too well was the largest issue I faced 😉. I kept that tank for a year or two and then decided that I would like to have some more room to play around with, as I figured out that I really liked to keep plants in the aquarium and that fish are more of a supporting element for me. So I upgraded to the tank I still have today, a 100 * 45 * 40 cm tank. Even though I have gone through multiple complete teardowns and re-designs since, I have never been able to get this tank nicely balanced for an extended period of time. Such a redesign of the tank usually happened at the point that I thought that there was no coming back from the current situation. Of course, trying the exact same thing again will likely result in the same outcome, so I did seek out local fish shops and help online in order to try and get my tank 'just right', which resulted in changes in lighting, filtration, substrate and fertilisers over the iterations. As you might have guessed however, I am not quite there yet.

So on to my current tank, first some details:
As I mentioned before, the current tank is 100 * 45 * 40 cm (I am assuming ~ 135 litre water).
The current setup is over a year old.
Filtration is done by a fluval 306
Lighting: 2 white 5050 SMD LED strips (60 leds / m, advertised as 1020 lumen per meter) and one RGB led strip that I use for coloration. These white strips are currently on for 8 hours a day at 50% output. Some months ago these were on 75% but I got algae issues so I decided to lower them. (I really wish par meters were cheaper so we could easily compare 'light intensity' between setups..) These strips are fixed to aluminium profiles which rest on the side of the tank, so a few centimetres above the water surface.
Substrate: Tropica aquarium soil.
CO2: No dosing (As a student I am really trying to keep cost down, so I'd rather not start CO2 dosing if possible)
Fertilizers: Two times per week NPK, two times per week micro. I started this specific dosing regime 5 weeks ago based on internet recommendations because I noticed holes forming in the older leaves which eventually completely broke down. I have the impression that the new dosing has significantly decreased this problem at least. The specific ratios I add: 1 ppm PO4, 10 ppm NO3, 15 ppm K per week (dry salts premixed, half on Monday, half on Thursday), and easy life profito for the micro side of things, a little higher than their recommended dose (15 ml, half on Tuesday, half on Friday). These numbers were advised by... a website that I can't remember at the moment...
Water changes: I change 50% of the water once per two weeks.
Fish: 15 Neon tetra's, 6 otocinclus (I would like to get some more) and one very shy Ancistrus.

On to the pictures of my tank.
Overview of the entire tank (sorry for the glare!)
View attachment 167541
Some closeups of plants that are not doing great:
Limnophilia: New growth looks nice and green, older growth (even close to the water surface) quickly turns brown (not the red tint you would expect from being close to the light if that is not clear from the image).
View attachment 167543View attachment 167544
Lotus: Some of the new leaves are still getting dark spots / holes / deteriated edges, even though there also plenty of leaves which look fine
View attachment 167546View attachment 167557
New growth on Rotala is also green (but I think rather small) and suffers from the same problems as Limnophilia with older leaves not lasting long.
View attachment 167550
Then, a plant that had been doing great until about a week ago, my Microsorum Pteropus Trident. About a week ago, I saw a grey / black spot on one of the leaves which seemed to spread (or they all suffered from the same unknown change in the aquarium) and almost completely obliterated the leaves on all the plants. I tried removing the affected leaves but it still spread /affected the other leaves as well. This is one of the few plants that seemed to be doing well before.
View attachment 167548
The plant I am trying to grow at the fron is the Marsilea Hirsuta. I knew beforehand that this plant was going to be a bit of an experiment but I am not sure what to do with it. On the one hand, the rough texture of the substrate makes it so that my Ancistrus regularly uproots these tiny plants. As you can also see the older leaves don't look great and BBA are starting to grow on/ near to these plants. However, I can also see plenty of new growth coming out from beneath the substrate. I have tried removing the worse looking parts, but I often uproot the new growth as well when doing so. Is there a future for this plant with my setup?
View attachment 167553
Finally, I would like to add a picture of some floaters I have, as perhaps some people experienced in the 'duckweed index' will be able to say something meaningful about my tank by looking at it, even though it is not duckweed 😉. I have also added a picture of my Echinodorus 'ocelot' as it has been getting extremely red new growth. I know coloration is also related to nutrients so perhaps someone is able to use this as some meaningful indication.
View attachment 167555View attachment 167556View attachment 167552

So that turned out to be quite a long read, thank you if you made it all the way here! As you can see from the images, plant health is far from optimal. I expect that the BBA and some minor other algae that I have been seeing are related to this fact. I also notice that I have a 'protein layer' (not sure what the correct english term is) on top of the surface. I tried to combat this with the custom spraybar that I made but I suspect the source of the problem is the leaves of the plants breaking down. I am currently working on getting a water report for my local tap water to see what elements are already in there.

As I mentioned at the start of my post, I have tried quite a number of things so far and I just can't seem to get consistent (even if slow) healthy growth. I am open to any suggestions people might have. If I missed anything that could help with giving advice, please feel free to ask and I will respond as quickly as possible.
Thanks for sharing your knowledge!
Cheers!

Disclaimer I have had a planted tank for only 8 weeks. I've never had a tank in my life
I'm sure someone will disagree with me and tell me how wrong I am...... In my experience I found co2 was what was missing in my tank. Now, I know you're on a budget and I too could not afford the fancy co2 injection kits. So I decided to go along the route of DIY sodium bicarb and citric acid. This was after weeks of waiting for non existent growth and lots of yellow and brown leaves. I couldn't even get monte Carlo to grow. Now I even have deep reds in the tank and a lot of overgrowth.

You will have read that no two tanks are the same etc etc but fundamentally plants need micro and macro nutrients (I use seachem flourish + fish waste), CO2 (I have a DIY setup), light (I have a red blue green light) and obviously water.
I also have cherry shrimp and amano shrimp in the tank they are grazing stuff off the plants. I am now intentionally blast my tank with light so I can get some algae for my amanos.

I almost forgot in classic rookie fashion I just poured this gravel, planted and hoped for the best but ended up retro planting some route tabs though I'm not sure how effective they have been.

Hope this helps.

 

[N00BIE]

I forgot to say this is a 210L tank and the total setup for co2 cost me £50 including the drop checker etc and running cost of £10 for the citric acid sodium bicarb which will need to be bought every 6 months or so. I have an external filter which dumps water above the diffuser resulting in "sprite water" but I don't mind because I can see that co2 is distributing nicely.

 

[N00BIE]

I forgot to say this is a 210L tank and the total setup for co2 cost me £50 including the drop checker etc and running cost of £10 for the citric acid sodium bicarb which will need to be bought every 6 months or so. I have an external filter which dumps water above the diffuser resulting in "sprite water" but I don't mind because I can see that co2 is distributing nicely.

 

[Lycolus]

Snip

Thanks again for the elaborate answer!

While I am working on implementing all the different suggestions given in this thread so far, I have a few more questions after doing some maintenance today.
First of all, I noticed quite a few of my floaters have the same dying / brown leaves :

As these are in contact with the air this shouldn't be a CO2 deficiency given the current lighting, which was suggested as the cause for the other plants not doing so great. So, is there something else going on as well? Any suggestions are welcome again!
Finally, I noticed quite a bit brown algae (?) in a number of places on the spraybar. I know these often turn up on tanks that are recently set up, but that is obviously not the case here. Thoughts?

edit: I also figured out how to add proper quality images lol 😅

 

[Lycolus]

Hey everyone, it has been some time since my last post and I have been working hard to implement all the changes suggested here, this entails the following:
-lights down to 40% then down to 30% (did not change the duration yet)
-Got a surface skimmer (the surface film is gone, this is of course a symptom approach but at least we can rule out that the film was preventing gas exchange with the water).
- Using the IFC Fert cal with the following dose:

GRAN TOTAL PPM (and % of CLONE TARGET)

NO3

N

PO4

P

K

Mg

Ca

CO3

HCO3

Cl

SO4

dGH

dKH

13.13

2.96

1.50

0.49

15.00

5.63

13.75

20.80

42.35

≈ 1.83 °

≈ 0.00 °

In addition, I still use PROFITO for the micro-side of the ferts.

The situation got a little better, but I am not quite there yet.
First of all, the Staurogyne repens has been becoming very pale. In real life they are even paler than they are on the foto I think. Is this a nutrient thing or are they getting too little light at 30% output? Personally, I think it's the light but I would like to get your input on this.

Second, I am still getting holes in leaves/ melting of the leaves afterward. Those ocelot leaves that are disintegrating in the picture were new growth in my aquarium. In the back of the lotus, you can also see the amazon sword species having the same troubles with the leaves. In the last picture, you can see that my floaters are also still having similar problems. As these are not CO2 limited, I suspect there must be something wrong with my dosing? The growth on the quick growers has improved quite a bit though after the light intensity got decreased further and the trident seems to have bounced back as well (sorry no pictures!).

Dosing:
I have been using MgSO₄, KH2PO4, KCl, and KNO3. I read a thread on here some time ago that sometimes (unknowingly) dry salts are sold under incorrect names. I can be pretty sure about the quality of the first 3 salts but the KNO3 is a bit of a wildcard as it comes from a different supplier. I have also noticed that my DIY mixture is having trouble fully dissolving even though the IFC calculator says it should be fine (10%, 1%, 5% and 5% of limit). I have been following the advice in the calculator to make no more than a month worth of mixture but I still noticed precipitation forming in the container. Is this a result of the dry salts not dissolving properly or is it perhaps mold? The container is kept in the far corner of my room so not cooled but out of any sunlight.

Could the quality of the ferts have anything to do with my lackluster plant growth or am I just trying to find problems? Should I change the dosing numbers? Any other advice?
Thanks once again for the input!

 

[John q]

Is this a nutrient thing or are they getting too little light at 30% output?

I doubt the paleness is being caused by to little light, infact the evidence with melting leaves, pinholes and green spot algae is actually suggesting to much light, if you've only just lowerd the setting to 30% then I'd let it run at that for a while and see if things improve, if its been at that setting for a bit then you might want to lower it a tad more.

You'd be surprised at how little light plants need to survive, the plants in these photos are in a low tech tank 1200mm that receives about 16w of light, more over the area that's pictured is completely covered with floating plants, while growth is slow, there is no sign of paleness.



I suspect the paleness to the plants and poor appearance of the floaters is being caused by lack of nutrients, I'd up the dosing of profito to at least 20ml a week and I'd also start adding an extra teaspoon of mgso4 to the tank weekly, just mix this with the water on water change day or add it directly to the tank.

Hope some of the above helps.

 

[Lycolus]

Thanks for the reply! It does seem a bit contradictory to me, however, as the Staurogyne repens seemed to do better before I started adding Mg (I wasn't dosing any at the time of my first post) and before I turned down the lights to the 30% which they are at now (and have been for some time). Growth on most plants has slowed down quite a lot but as I stated in my first post, I am running out of ideas so I'll try your suggestion of reducing the lights even further and I'll also increase the dosing of the profito. I would appreciate it if any other people could chime in with their thoughts though.

 

[John q]

Thanks for the reply! It does seem a bit contradictory to me

The truth is I'm guessing at what will help fix your tank, its an educated guess based on experiences I've have had with my tanks, but its a guess non the less.

I've a long history with fish only based aquariums, but not with planted tanks. When I first set up a plant based aquarium I stumbled across a really good article by Tom barr and the headline I took, and remember to this day was "Try it and see."

I'd love to tell you to do 3 cartwheels and sing hallelujah and suggest that this will make your plants grow quicker, but I'd be lying.

If you have an incline that increasing the light intensity will improve the faults that are present in the above photos then try it, my advice could well be wrong.

Just remember all the advice you get is merely that, its sometimes better to go with your gut instincts and monitor the effects, at least this way you'll build a knowledge base, based on your own experiences and not hearsay or fiction 😉

 

[Lycolus]

I'd love to tell you to do 3 cartwheels and sing hallelujah and suggest that this will make your plants grow quicker, but I'd be lying.

I would get a lot of singing if this would work!

Either way, I am grateful for the suggestions you offered so I lowered the light intensity further and I'll see what happens. English is not my first language so perhaps my previous message did not come over entirely as I intended it to sound. I'll report back here in some time.

 

[John q]

No offence taken @Lycolus and sorry if my retort seemed touchy (which on re reading probably did)

I'd see if the extra ferts and lower light make any difference and if there's no improvement in a few weeks then move to plan b.