HC & Staurogyne Repens turning dark?

[Seoulstar]

Hello,

Trying to see what could be the issue with my tank as the color of the HC are turning dark yellow, and the inside of the SR leaves are also turning black/dark.

I have pressurized CO2, using aquasoil and dosing Flourish, Flourish Advance, liquid CO2...etc.

 

[ceg4048]

Hi,
I cannot tell from the color balance of your photos. Are the mature leaves turning yellow or are the new leaves?
Leaves turning dark is a CO2 issue.

Since you are dosing Liquid CO2 as well as gaseous CO2 there are a couple of different reasons:

A. Poor flow and/or poor distribution of that flow.
B. Poor injection rate
C. Too much light.
D. All of the above.

Yellowing is caused by poor Nitrogen or by poor trace element or poor flow/distribution.
I see nowhere specified whether you are adding NPK. This is OK if you are using brand new Aquasoil, but if it is used then you might need to supplement NPK.
Also, FYI that Flourish Advance is costing you much more than it is giving you. I would ditch that immediately. Maybe sell it to someone else who thinks it might be useful.

The easiest first step is to reduce the light intensity. You did not state what kind of lighting you have, but if I had to guess, like 95% of folks, I'd hazard that you are killing the plants with lights that are too bright.
I don't know the size of the tank or the manner which your output spuds are so I can't comment until I can see a photo of that.
Also you have not given any details about your filter throughput.

It is a painful irony that the biggest problem in a CO2 injected tank is poor implementation of CO2.

Cheers,

 

[Roediger]

Clive, Leaves turning pale on pogostemon helferi is a co2 issue as well?

 

[ceg4048]

No. as I mentioned in 3rd paragraph, this is a nutrient issue. Poor nutrient uptake can be a result of either poor dosing, poor flow/distribution, excessive lighting, or, if the cause is micronutrient shortage, poor chelation.


Cheers,

 

[Seoulstar]

Hi,

It is a painful irony that the biggest problem in a CO2 injected tank is poor implementation of CO2.

Cheers,

Hi Clive,

As always, thank you for taking the time to give your input.

I took some more photos in hopes of better color rendition but unfortunately, I don't see any improvements lol.

I think I have decent flow/distribution as the scape itself is not high and I can see the bubbles hitting all the spots.

The CO2 turns on 2 hours before the lights come on, and the 4dkh drop checker usually turns green @ 3-4 hour mark.

Too much light - this could be the issue so I have decreased the light one stop to see if it will improve. You will also notice the light is right above the water and not suspended like the usual setups.

It's a Chihiros LED and looking at how the HC is growing low, I think the lighting is sufficient, though cannot say the same about the quality.

I set up this tank late November so the soil is relatively new but I do dose a local 2 step fertilizer, which unfortunately does not include information on the contents (but is widely used in my country)

I was hit with hair grass algae couple weeks ago but fortunately got rid it of it.

There is no other significant algae at the moment, so the main issue basically is the coloring of the plants.

The HC is yellowish and green and the leaves look unhealthy (skinny per se). SR is doing okay, just some blackening of the leaves near the center of the plant and around the edges of the leaves.

Meanwhile the hairgrass is well, no issues there.

So I'm going to take your advice and reduce the light and see how it goes for the next two weeks.

 

[Roediger]

No. as I mentioned in 3rd paragraph, this is a nutrient issue. Poor nutrient uptake can be a result of either poor dosing, poor flow/distribution, excessive lighting, or, if the cause is micronutrient shortage, poor chelation.


Cheers,

Whoa wish I saw your reply before making a thread of my plants. my bad. I read your dry salts thread, and went ahead and made a new mix Thanks again.

 

[ceg4048]

Too much light - this could be the issue so I have decreased the light one stop to see if it will improve. You will also notice the light is right above the water and not suspended like the usual setups.

It's a Chihiros LED and looking at how the HC is growing low, I think the lighting is sufficient, though cannot say the same about the quality.

Hi Seoul,
I agree that your flow/distribution is OK, and that is the reason the HC is growing low. Light has nothing to do with making HC grow low.
So we can try to narrow the cause down some more, but for that you will need to take a series of pH measurements as explained in a very old thread=> https://www.ukaps.org/forum/threads/melting-marsilea-hirsuta-staurogyne-repens.28996/

Record our pH profile data and report back. The pH profile gives you a "fingerprint" of the behavior of the gas.

Cheers,

 

[Seoulstar]

Hi Seoul,

Record our pH profile data and report back. The pH profile gives you a "fingerprint" of the behavior of the gas.

Cheers,

Hi Clive,

I read through the old thread and will record the PH profile data as you suggest.

Were the PH records done through just a normal test kit or with some other measurement device?

 

[Edvet]

You'll need an electronic pH device, like a pen or probe.

 

[ceg4048]

Were the PH records done through just a normal test kit or with some other measurement device?

You'll need an electronic pH device, like a pen or probe.

Well, depending on the resolution of your color scale and the acuity of your eyes, you don't really "need" a pH pen, but it certainly give you better information and is a LOT easier to use.
As much as people in this hobby winge about pH it's shocking to know how few actually own a high quality pen or probe.
In any case, use your kit to the best of your ability. You should definitely be able to tell if you have a 1 unit drop. The intermediate values are less important.

Cheers,

 

[Seoulstar]

Well, depending on the resolution of your color scale and the acuity of your eyes, you don't really "need" a pH pen, but it certainly give you better information and is a LOT easier to use.
As much as people in this hobby winge about pH it's shocking to know how few actually own a high quality pen or probe.
In any case, use your kit to the best of your ability. You should definitely be able to tell if you have a 1 unit drop. The intermediate values are less important.

Cheers,

Hi Clive,

Sorry took so long to post my findings.

Anyways I measured the PH in the morning and it was at 7.2, which I assume would remain the same before the CO2 starts. My CO2 starts at 4pm and the lights come on at 6pm. I just got back from work (6pm) and the current Ph is 6.0.

Would the above information at least provide some indication as to if there is enough CO2?

I have decreased the light intensity since your last response but still see no visible improvement. I will post pictures soon.

 

[Edvet]

A 1.2 point pH drop would be sufficient, still leaves the possibility of inefficient distribution. Decreasing light intensity is always a safe move in case of problems. Now keep it like this, do correct maintenance and re-evaluate after 6 weeks.

 

[ceg4048]

Anyways I measured the PH in the morning and it was at 7.2, which I assume would remain the same before the CO2 starts. My CO2 starts at 4pm and the lights come on at 6pm. I just got back from work (6pm) and the current Ph is 6.0.

Would the above information at least provide some indication as to if there is enough CO2?

Hi, yes, as Edvert mentions, it's good that you are getting a 1 unit drop, but I can't recall if you provided your KH. If the water is very low in carobnates you might need a biger drop. If your KH is above 5 or so then 1.2 drop is good.

In any case, yes the best policy is to minimize the lighting for now. Remember to do large and frequent water changes...if you can.
Sometimes we use so much light that it is difficult to compensate so we need outrageous amounts of CO2 to enable the plants to resist the damage caused by the lighting.

Cheers,

 

[Seoulstar]

Well, depending on the resolution of your color scale and the acuity of your eyes, you don't really "need" a pH pen, but it certainly give you better information and is a LOT easier to use.
As much as people in this hobby winge about pH it's shocking to know how few actually own a high quality pen or probe.
In any case, use your kit to the best of your ability. You should definitely be able to tell if you have a 1 unit drop. The intermediate values are less important.

Cheers,

Hi, yes, as Edvert mentions, it's good that you are getting a 1 unit drop, but I can't recall if you provided your KH. If the water is very low in carobnates you might need a biger drop. If your KH is above 5 or so then 1.2 drop is good.

In any case, yes the best policy is to minimize the lighting for now. Remember to do large and frequent water changes...if you can.
Sometimes we use so much light that it is difficult to compensate so we need outrageous amounts of CO2 to enable the plants to resist the damage caused by the lighting.

Cheers,

Hi Clive,

Thanks for your input. My KH is 2 so then 1.2 drop is not good I assume?

I just did a 50% water change yesterday, dosed Seachem Flourish and nothing else. Nitrates are reading low so will go home and re-check the nitrate levels and will dose KNO3 if required. (yesterday I checked it was at around 5 ppm).

 

[ceg4048]

Hi Seoul,
Yeah, that's the problem with low KH water - it's deceptive because it has such low buffering power than small amounts of acid can drop the pH by a large margin. You may need to drop it by more, maybe 2 or more units to show the proper CO2 saturation.

You can try to carefully increase the injection rate (so you do not gas your fish) until you approach a 2 unit drop by lights on.

Cheers,

 

[rebel]

Do you think it's mild GSA that's appearing rather than darkening of leaves? Do you have GSA increasing elsewhere?

 

[ceg4048]

Yeah, it's probably GSA, but even so, GSA is a CO2 and/or PO4 issue so the corrective action ought to be the same.
Seoul also reported hair algae previously, so there's plenty implications of chronic CO2 shortfall.
There is definitely a problem with nutrients as he is not following a correct dosing program (checking for nitrates and so forth will get hobbyists nowhere) but that is Aquasoil so there should not be an issue unless the sediment is old and is depleted of nutrients. Since he is not dosing there can be all kinds of NPK shortages and the plants are yellow which tells us more than any test kit could dream of doing.
Definitely needs to fix the CO2 though and then it might reveal an even more acute NPK shortage.

Cheers,