Above 8

[hax47]

I am not sure where this journal will go. I have a few aquariums and would also like to set up a new one soon, but I want to keep a single journal. I guess I am not a skilled aquascaper; I wish I had more of a feel for the artistic angle of aquaristics. So I focus more on the biology/chemistry side of the hobby... I will try to write down my thoughts and experiences with my aquariums, and hopefully, I will also get some insights from the community. I also plan to do a few experiments here and there, mainly to have a closer look at the things that I am interested in at the time.

A little bit about my tanks...
I keep all my tanks low-tech using tap water, which has a hardness of 24 (GH) and 12 (KH). That results in pH values above 8, hence my journal title. It seems to me that keeping plants in soft/low pH water could be more rewarding, but I use my cichlids as an excuse for my stubborn insistence on tap water. Also, I change about 500 liters of water on weekends and like to keep the process simple and fast. So diluting the water with RO water is excluded, at least for now.

I add dry salts in all my tanks, using a single weekly dose of 10 ppm of NO3 (KNO3), 1 ppm PO4 (KH2PO4), and ~17 ppm K (10 from K2SO4 and the rest from the other two). With a 50% weekly water change and low lighting, I expect to have concentrations around double these values in the water. Until a week ago, I dosed Fe-DTPA only (0.1 ppm per week) as a micronutrient and hoped that the tap water would contain all the others. Then I started dosing other micronutrients last week for no reason except that it shouldn't hurt, and who knows, maybe my plants miss something. I realized that my plants might have iron deficiency, so I also increased the Fe-DTPA and started dosing a bit of Fe-EDDHA; that one I add separately. The plan is to add just a little bit until I start seeing some pink coloration in the water. My color blindness does not make the task trivial, though... 🙂

This is my DIY micronutrient mix. I'm not sure if there are any major flaws in it, but I guess dosing some of everything besides iron gets the job done:

Fe-DTPA: 0.2 ppm Fe
Borax: 0.03 ppm B
Zinc sulfate: 0.02 ppm Zn
Manganese sulfate: 0.05 ppm Mn
Na2MoO4: 0.0015 ppm Mo
CuSO4: 0.0015 ppm Cu

I mixed these elements in 2% acetic acid to get the indicated ppms after adding 10 mL into 100 liters of water. I split this amount into three doses during the week.

 

[Guest]

I am not sure where this journal will go. I have a few aquariums and would also like to set up a new one soon, but I want to keep a single journal.

Here is perfect. Your tank in the members introduction thread looks amazing. so looking forward to seeing and reading more 😉

 

[hax47]

Here is perfect. Your tank in the members introduction thread looks amazing. so looking forward to seeing and reading more 😉

Thanks, Tim, for your kind words.

A little bit first about my other aquarium, a 160 l shallow one. I started it with the dry start method and added water in early June. This one is also equipped with an undergravel filter, a cheap 6000K LED light, and has basalt and crushed lava rock gravel. Under the Eleocharis plants, there is some potting soil under the gravel; there is no UG filter there. I keep my Cyprichromis fry inside and some Amano and cherry shrimp.



I was surprised by the absence of algae problems for some time, but those times might be over; they appeared just after I started dosing iron more often and adding some Fe-EDDHA:



I guess I need the iron though... the new leaves on Staurogene, Pogostemon, and even on the moss seem a bit pale to me. Not sure what the pogos should look like, but the whitish leaves in the middle are suspicious to me. Given the high pH, iron deficiency could be the problem here:



I have read about the duckweed index here, so I took a photo from above to assess it:



I am unsure about the index value in this case, but I believe it falls into the not-dark-green-enough level ?? Maybe I should come up with some dark-green duckweeds to have a calibration standard to be able to compare them ....

My anti-algae plan now is the following: I will keep the new iron dosing regime (0.2 Fe-DTPA divided into 3x doses per week supplemented with Fe-EDDHA), already trimmed back the leaves with algae and dimmed the light to about 50%, and will change water 2x a week. If everything seems good after a few weeks, I will ramp up the light slowly. Luckily my lights have a dimming feature 🙂



Since CO2 delivery might also lead to algae problems, I am trying to get some idea about how effective the flow and CO2 exchange with the air is. Hence the drop checker in one of the photos. The solution inside has a 0.4 KH, so it should turn green at around 3 ppm of CO2. I am not concerned with the absolute level of CO2 though; instead, I want to compare the CO2 partial pressure in my tank to that of the air. I expect them to be the same if the tank is well-aerated. So I have two calibration vials. One contains the same solution, while the other has a bicarbonate level corresponding to 1.2 KH, simulating the color of my drop checker if the tank had only one-third of the atmospheric CO2 pressure. Both are equilibrated with air. That way, if I compare the colors with my drop checker, I get an idea of how well the water is supplied with CO2:


The left vial corresponds to the atmospheric CO2 level; the right one simulates the 1/3.

I have tried a few drop-checker positions already, but thus far, I have not observed any regions in my tank with restricted CO2. All areas appear to be well supplied. It might be a good idea to try in another aquarium with lots of plants/or algae to see how low one should go with the flow/up with plant mass to get low CO2 levels during the photoperiod. I am curious.

 

[hax47]

It does apply to CO2. The other forms of carbonate species, bicarbonate and carbonate, are determined in the equilibrated system by pH but the level of dissolved CO2 gas remains constant. Non-equilibrium factors can affect dissolved CO2 levels, including for example respiration by animals, photosynthesis by plants, decomposition of organic matter and of course, delibrately bubbling CO2 gas into the water column. Absent any active processes, dissolved CO2 is heading for 0.5 ppm.

Andy's comment made me realize that my drop-checker makes little sense regarding the local CO2 levels during the photoperiod. The gasses' diffusion rate depends on the partial pressure difference between the air and the solution, and at low CO2 levels, the difference between the two compartments is quite small. This means that reaching the equilibrium should be a much slower process than in high-tech aquariums with bigger CO2 differences. So my indicator color probably just shows an average CO2 during the day and is not quick enough to follow the changes during the photoperiod.
Still, I am confused with the color of the calibration indicator, which I expect to be green at 3 ppm levels. But that could just mean that I need to leave my vials open for a prolonged time, maybe days, to really get an equilibrium with air. Definitely, something I should try.

 

[hax47]

A good feature of the Fe-EDDHA is that you can watch its distribution in the aquarium, making the water flow visible. So I watched it. The red dye reached the right side of the aquarium in about a minute, creating smoke-like structures above the gravel. It was like a frozen image; there was hardly any water movement. I could not take a good picture; the smoke was too faint to be visible in the photo. The under-gravel filter does not cover that part of the tank, and the Vivipara also blocks the flow. This part of the aquarium is that:

I have an extra outlet for the filter behind the right stone group, which is now plugged in to prevent short-circuiting the water flow. I can attach another pump to make some flow there as well. I think I should.
Interstingly, the drop-checker is still green, so the averaged (over 24 hours) CO2 in the aquarium should be around 3 ppm:

And it is now actually brighter than my calibration solution:

I think it is the calibration solution that got darker with time. It is equilibrating further with the air after I thought it was already in equilibrium.

 

[hax47]

I was not home for 5 days, and it looks like something grazed my moss and S. repens. Some of the moss branches have lost their leaves, but only on one rock, next to the S. repens:

My single S. repens plant, before and after:

My suspects are the Amano shrimps or the snails. Maybe they do not like fasting for a few days? Or they don't like the lower light intensity? Still, losing the leaves in 4 days seems to be a bit fast.

 

[Hufsa]

I was not home for 5 days, and it looks like something grazed my moss and S. repens. Some of the moss branches have lost their leaves, but only on one rock, next to the S. repens:

My suspects are the Amano shrimps or the snails. Maybe they do not like fasting for a few days?

Unless youre also hiding some Siamese Algae Eaters in there, you can consider the Amanos guilty as charged 😅

 

[hax47]

Unless youre also hiding some Siamese Algae Eaters in there, you can consider the Amanos guilty as charged 😅

And yet, they look so innocent 😳

 

[hax47]

This one is the 900-liter tank I posted a picture in the introductory thread. The size is 250x60x60 cm. It has an undergravel filter run by three powerheads (1300 l/h each). It is built using prebuilt UG filters and some lawn grids in the middle. The cords of the powerheads were too short; therefore, I had to put them on the right side and attach the intake and the outlet to pipes going to the middle and left sides. I covered the grids with plaster mesh to prevent basalt gravel from falling into the holes of the lawn grid:





There is also an inner filter on the right side; I took that one from another matured tank to help with the cycling period.


I start getting some algae after three weeks, but the water seems to be quite clear from the side:

I only have four 15W Sansi bulbs for lighting.

 

[hax47]

I was reading about putting dried leaves into the aquarium. It has been discussed on this forum previously. An interesting topic, Christian Steinberg says, that humic acids released from the leaves benefit the aquatic life even at concentrations they do not cause too much coloration. Eventually, I searched if Lake Tanganyika had any humic acids. Humic acids can be washed into lakes from the ground even if the leaves do not directly fall into the water. And I ran across this paper:

The Effects of Humic Acids on the Early Developmental Stages of African Cichlids during Artificial Breeding

The aim of this study was to compare the effect of humic acid (HA) obtained by extraction from alginate on the incubation of roes and fry development in African cichlids, Labidochormis caeruleus, as well as their influence on the stabilization of the physicochemical parameters of water in an...

www.mdpi.com

There are a few strange things with the study (measuring the water parameters with a test strip in a research study, for example), but the thing that caught my eye is that they kept the fish fry in 10 l aquariums equipped with an air stone only (and the temp was held stable). As expected, there were casualties; 14 out of 40 in the control group died by day 30. With humic acid supplementing (5-10%), the mortality decreased to 3-4 out of 40. It is unclear whether this is the humic acid's direct effect because the nitrite levels were drastically different. And that is what I find interesting here, the tanks with no filters, but humic acid (HA) supplement, had lower nitrite (5 vs. 0.1 ppm) and lower nitrate (!!) as well (100 vs. 30/20/10 ppm depending on HA concentration). I am unsure if I should believe this, although even a test strip should be good enough to discriminate between 100 ppm and 10 ppm. Does anyone have an idea what happened with the nitrogen in this study?

 

[_Maq_]

And it is now actually brighter than my calibration solution:

The water in the tank can easily get oversaturated with CO2 due to microbes' respiration.
A few years ago, I've tried to get some numbers. With primitive tools, I concluded that several units of mg/L (3-5) CO2 are the norm (compared to cca 0.5 mg/L equilibrium with air). I cover my tanks with glass, and I believe it also contributes to the elevated levels of CO2.
Also, in living spaces, concentration of CO2 in the air can be significantly higher than the norm.

 

[hax47]

The water in the tank can easily get oversaturated with CO2 due to microbes' respiration.
A few years ago, I've tried to get some numbers. With primitive tools, I concluded that several units of mg/L (3-5) CO2 are the norm (compared to cca 0.5 mg/L equilibrium with air). I cover my tanks with glass, and I believe it also contributes to the elevated levels of CO2.
Also, in living spaces, concentration of CO2 in the air can be significantly higher than the norm.

I agree; in the other thread, I try to tackle these questions a little bit. It seems that the in-room CO2 level is indeed higher than what would result in 0.5 mg/l equilibrium, but there are some uncertainties regarding the constants, and there are still some missing controls (e.g. CO2 equilibrium outdoors).
I was just thinking about the effect of the tank cover today, might just include some experiments for that too.

 

[hax47]

Amanos feeding fish:

 

[hax47]

The first time my anubias is blooming. The first flower gave up (the left one), but the second managed to open up:

 

[hax47]

It has been a while since my last update on tanks, so here it goes. In the smaller tank, the last time, I was getting algae on the dwarf hairgrass, which I attributed to the changed dosing and lack of good circulation on the right side of the aquarium. I decided to dim the light and install a new pump. After dimming, my Pogostemon started to lose the bottom leaves and became elongated a bit, but the hair grass did not improve. So I stopped dimming and even increased the macro dosing by 50%. I suspected initially that the increased iron dosing had a toxic effect until the plants started to acclimate to it, so I started adding ascorbic acid to the micro-dosing regime. I also put some humic acid on the same days. Both of them are close to homeopathic doses, I am not sure if they help in any way, but I am happy with how my plants do now, so I'll just keep them. In retrospect, I think the hairgrass algae was due to the melting because they went from emerged to submerged form. It seems that slowly all of them died back, and fresh, smaller leaves started to appear:



The Vivipara also died back spectacularly, although I had the impression that it grew quickly in the first month or so after filling up the tank.

I will see if it dies back completely or if something remains. I am curious. I also upgraded my duckweed frogbit index. I think it looks good, I might have a good fert dosing regime now. I had to harvest the index two times in 10 days; it just went crazy:



My wife kept telling me that I needed some red in the aquarium; it was just too green, and nothing broke that color. So I bought some Ludwigia spec. Red, Alternanthera reineckii 'Mini' and Rosanervig. I am unsure if I like the big leaves of the Rosanervig, but I will let it and see how it evolves in my tank. If it dies, that will solve my doubts:



With the AR Mini, I was encouraged by Andy Pierce's Shrimphaus, which has this plant and is thriving in alkaline waters. Interestingly, some of the stems seemed to be in a bad initial shape compared to others:



And then came my shrimps, and downvoted the bad-looking ones in two days while not touching the healthy ones:



Btw. shrimps: I am amazed how these little creatures keep my little garden clean. I have never had shrimp before. I wish I could put them in the 900l aquarium as well. There was a baby boom in the RCS community; I wonder what I will do with them once they fill the tank.

Together with the red plants, I also tried to select a few plants with small leaves to fill some empty gaps in the aquarium:
Hydrocotyle tripartita Mini
Myriophyllum sp. Guyana
Ranunculus inundatus



I will see if any of these remains. The shrimps have not said anything yet about these; they might still be evaluating the integration process of these newcomers.

This is the tank now:

I left some headspace and made a top with tighter fitting; now, the aquarium keeps the CO2 levels for two days after the water change; it goes from ~10 ppm down to 4 ppm during this period. I also tried last week to dose the micros diluted in sparkling water; I got a similar CO2 pattern with 200 ml volume as with the water change CO2 swings.
If I decide to keep the headspace, I will need to hide the water level somehow.

 

[dw1305]

H all,

I also upgraded my duckweed frogbit index. I think it looks good, I might have a good fert dosing regime now.

They look <"pretty good">, I'm guessing that you are supplying all the mineral nutrient requirement of your plants and are at @Parablennius's "sweet spot" - <"Floaters">

cheers Darrel

 

[hax47]

H all,

They look <"pretty good">, I'm guessing that you are supplying all the mineral nutrient requirement of your plants and are at @Parablennius's "sweet spot" - <"Floaters">

cheers Darrel

Thanks, Darrel, and thanks for the invention of the index; I like it! The plants do not grow as big as @Parablennius's, but they are the best I could achieve so far, and I am happy with them now.

 

[dw1305]

Hi all,

and thanks for the invention of the index; I like it!

I'm <"proud of it">, but it isn't really my invention, it is a <"cut and paste job"> from earlier research. Some non UKAPS people, who <"keep Apistogramma etc">, are using it now.

I think it is particularly suitable for people who want plants, but don't want excessive growth or to use EI etc. I think plants are the gift that keeps giving, in water quality terms, so if you keep sensitive fish it makes sense as an approach.

cheers Darrel

 

[hax47]

I'm <"proud of it">, but it isn't really my invention, it is a <"cut and paste job"> from earlier research. Some non UKAPS people, who <"keep Apistogramma etc">, are using it now.

I think that taking knowledge and ideas from one field and developing it to be applicable in another is still quite innovative.

 

[hax47]

From the new plants, some survived, some did not. Ranunculus inundatus disappeared, but Myriophyllum sp. Guyana is still alive, even grown a bit, although it lost the leaves on the bottom:

The Ludwigia is barely alive, and the AR rosanervig seems to be struggling a little bit, but I am not sure if it is going in one or the other direction:

In this part of the gravel, the water flow is relatively high, so it might be that they do not like it. Anyway, I bought a new Ludwigia and have it floating for now. If it does well, I will plant it.

The Hydrocotyle tripartita mini grows well, though:


I also planted some HM and Monte Carlo, and some rotala in the background to hide the powerheads. I am curious about what sticks from these.


I replaced the lamp with DIY lamps, with 6500K/95 CRI led strips. Now I can have higher intensity and control the intensity/lighting cycle through the home assistant. Overall, I think the tank is doing well at the moment:



I have struggled a little bit with fertilization. GSA started to appear, so I increased the phosphate dosing to 3 ppm/week, and the GSA disappeared. Then I started having these pale new leaves, I probably precipitated the Fe.


Also, they had a few holes.

So I changed to daily micro dosing and I dose a little bit more, and have kept dosing micros diluted in carbonated water (made with sodastream):


Now, the frogbit seems to have less chlorosis, but the leaves are a bit curly and they still have a few holes. I am not sure if these are new or left there from before.



This is the 900 l tank; it has some brown algae here and there, but it is getting better: