Seeking help for declining plant health …

[*Ci*]

Hello group!

I need help in figuring out why my plants are unhappy. They have recently been developing algae including bba , and also some yellowing and rotting of leaves. They look unhealthy, certainly not thriving and I am trimming off half dead or algae ridden leaves every week, with very little new growth.
This is in my discus tank:
A Symphysodon Symphony

Current photos of some of the afflicted plants:


Pinto anubias:



The pinto anubias from last November (how nice they were!):



History
- This was an established middle energy tank with low demand plants (large leafed anubias, small pinto anubias, crypts, java fern, sword), set up in 2023. Plants have been healthy, growing, algae free.


Switched tank over to Discus (Jan. ‘25)

• removed substate & potted the crypts and sword
• gradually raised temp from 74F to 84F
• started 3 x 50% water change’s per week instead of 1x for a few months, now backed down to 2x per week
• stopped adding macros after the first couple of months as the levels in the tank have risen with the larger fish and feeding load.
• front load micros 2x per week after each water change’s.
• did not change filtration, lighting or c02.
• added air stones to run at night

The tank is bare bottom with a continuous sweep pipe to keep it clean; pre-filters on the 2 canisters are each cleaned weekly. The sides and bottom are wiped weekly. I’ve been using a dose of Excel with each w/c in an attempt to combat the BBA , which is also on some pipes and hardscape.

I would consider this tank super clean, which is necessary for the discus.

I just did some new water tests today:

Before water change:
N03 = 20-30ppm (API) … 25ppm (Salifert)
P04 = .5-1ppm (Salifert)
K = 10ppm (Salifert)
Ph = 6.8-7 (API)
kH = 2 dkH (API)
gH = 4 dgH (API)

I add baking soda, magnesium sulphate and calcium chloride with each water change to maintain those levels, since my tap has zero kH and gH. I also add a dose of almond leaf powder to add a slight tint to the water (which I prefer) but also for some possible health benefits to the fish.
C02 is kept at about a .5 to .8 pH drop via a Yugang open flow reactor and is on 24/7 for stability.

After water change (no added macros);
N03 = 10-20ppm (API), 5-10ppm (Salifert)
P04 = .5ppm
K = 15ppm (not sure why that would go up)
kH, gH, pH, all the same after additives during refill to bring them up.

Possible problems?

• Plants just don’t like the warmer temps and are finally showing it? But these are plants that many seem to do fine with in discus tanks.
• Something to do with my fert regime?

I don’t know what to try without hurting the discus, but I really don’t like what is happening to my pinto anubias, especially. They were the showcase plant of the whole tank and I don’t want to lose them!
Any advice or insight would be welcome!
A Symphysodon Symphony

 

[Pepere]

I am assuming you have already checked the Anubias rhizomes for any sign of rot…?

 

[*Ci*]

I am assuming you have already checked the Anubias rhizomes for any sign of rot…?

Yes and the rhizomes look fine at this point.

 

[Yugang]

did not change filtration, lighting or c02

To have a complete picture, can you summarize what you're doing with CO2? There are of course many possible causes, but statistically CO2 is often guilty so it makes sense to double check.

 

[*Ci*]

To have a complete picture, can you summarize what you're doing with CO2? There are of course many possible causes, but statistically CO2 is often guilty so it makes sense to double check.

I put in an open flow (spray bar) diffuser about the time that I removed the substrate but before I added the discus. It is giving me around a .8 drop in pH which is what I thought would be best for these low energy plants and not too hard on the discus.
Prior to that, when the plants were healthy, and the tank was just a regular tank with sand/small gravel substrate and lightly stocked community fish, there was no C02.
Here is a picture of the tank with the open flow diffuser, before I added discus. The plants looked great!

 

[Yugang]

I put in an open flow (spray bar) diffuser about the time that I removed the substrate but before I added the discus. It is giving me around a .8 drop in pH which is what I thought would be best for these low energy plants and not too hard on the discus.
Prior to that, when the plants were healthy, and the tank was just a regular tank with sand/small gravel substrate and lightly stocked community fish, there was no C02.
Here is a picture of the tank with the open flow diffuser, before I added discus. The plants looked great!
View attachment 8343

Just to make sure that CO2 is not the problem, the following questions:

Have you checked CO2 stability?
Are you using the CO2 Spray bar in overflow mode? If so, how often do CO2 bubbles escape?
It looks like your tank is about 75 gallons or so, how early do you start injecting CO2?
Does the tank, and the CO2 Spray bar have a decent flow? At least not stagnant at tank surface or below CO2 Spray Bar?

If you are not using overflow mode, the rate of injection will depend on the CO2 rate as from the CO2 regulator. Have you checked you bubble count and is it stable?

Will send you a PM @*Ci* , to make sure we can rule out CO2 as root cause for the declining plant health.

 

[Phish Tank]

First off, really sorry to hear your plants are struggling. A few random thoughts….

I wonder about the no macros ferts. I mixed up my last batch of ferts with only half the nitrates because fish food does contribute some of that. Anubias are potassium hogs, maybe they need more.

@Burr740 made an insightful (as usual!) Post in thread 'Current thinking on the Ca:Mg:K ratio?'. Maybe a nugget in there that will help?
Question of the Day - Current thinking on the Ca:Mg:K ratio?

You didn’t mention what your Ca:Mg target is for your remineralizing, and I’m guessing you are still dosing micros, maybe post those amounts too.

 

[*Ci*]

Just to make sure that CO2 is not the problem, the following questions:

Have you checked CO2 stability?
Are you using the CO2 Spray bar in overflow mode? If so, how often do CO2 bubbles escape?
It looks like your tank is about 75 gallons or so, how early do you start injecting CO2?
Does the tank, and the CO2 Spray bar have a decent flow? At least not stagnant at tank surface or below CO2 Spray Bar?

If you are not using overflow mode, the rate of injection will depend on the CO2 rate as from the CO2 regulator. Have you checked you bubble count and is it stable?

Will send you a PM @*Ci* , to make sure we can rule out CO2 as root cause for the declining plant health.

I sent a pm, but I’ll post my reply here as well, to keep all the information available to everyone:

Hi yugang, Thank you for your help in this matter.
The tank is 84g and yes, I am using overflow mode. The bubble escapes maybe once every 2 minutes.

I run the c02 24/7 so no ramping up time. The tank has good flow with 2 Oase 850 canisters going to spray bars aimed a ross the tank surface. The c02 reactor sits above one of the spraybars so that the flow is directly below the opening.

It all seems to be stable, but I have not checked the pH drop in a while - I will do that.
Also, these plants were thriving for a year or so when I had no c02 on the tank, I only added the reactor recently, when I started the conversion to a discus habitat.

 

[*Ci*]

First off, really sorry to hear your plants are struggling. A few random thoughts….

I wonder about the no macros ferts. I mixed up my last batch of ferts with only half the nitrates because fish food does contribute some of that. Anubias are potassium hogs, maybe they need more.

@Burr740 made an insightful (as usual!) Post in thread 'Current thinking on the Ca:Mg:K ratio?'. Maybe a nugget in there that will help?
Question of the Day - Current thinking on the Ca:Mg:K ratio?

You didn’t mention what your Ca:Mg target is for your remineralizing, and I’m guessing you are still dosing micros, maybe post those amounts too.

I thought about mixing up a low/no nitrate solution, but then I finally found a Salifert Potassium test kit (they were out of stock in all of Canada for several years!) and saw what my K levels were.
I base my levels on what rotala butterfly suggests for a low light/weekly Ei dose, which is:
N03 =10ppm
K = 10ppm
P04 = 1ppm

So, without dosing macros, my levels are here (fluctuating a bit depending on before or after a 50% water change):

N03 = 10-20
K = 10-15
P04 = .5 - 1

That seems spot on for a low energy tank, but maybe I’m wrong? These levels are what I used to dose to when I did once a week, front loading before I switched to discus and the plants were thriving. They are also what I dose to in my other low energy tank, without normal fish (lol) and those plants are thriving.

I am dosing csm+b micros as per rotalabutterfly as well - 1ppm Fe, plus a squirt of Seachem Iron, 2x a week after water changes.
I’ll take another look at the CA:MG:K article, thanks for bringing that up.
And thanks for giving my problem so much thought, I really appreciate it and hope I can find a solution.

 

[Koan]

That seems spot on for a low energy tank

Yes but 10° increased heat has increased the energy in your system.. even Anubias are going to metabolize faster at higher temperatures. Everything does.

Maybe that's part of the issue?

 

[*Ci*]

Yes but 10° increased heat has increased the energy in your system.. even Anubias are going to metabolize faster at higher temperatures. Everything does.

Maybe that's part of the issue?

Oh, I didn’t know that would be an effect of higher temps. So, what would be the suggestion here, given that the discus folks recommend a low a nitrate level as possible. Maybe try increasing my doses of P04 and K only?

 

[Burr740]

Yes but 10° increased heat has increased the energy in your system.. even Anubias are going to metabolize faster at higher temperatures. Everything does.

Maybe that's part of the issue?

Oh, I didn’t know that would be an effect of higher temps. So, what would be the suggestion here, given that the discus folks recommend a low a nitrate level as possible. Maybe try increasing my doses of P04 and K only?

That 10 degree rise is huge. Everything goes faster, waste gets more toxic (to plants) Around 80 is the cut off for a lot of plants we keep to do well. Some plants can handle higher temps, many cannot. I dont know what that list looks like tbh, but you may have to narrow down some species and just accept it

Something else to consider is how plants respond to changes. Plants are always wired for their current conditions. It can be dramatic, like emersed to submerged, co2/no co2, or more subtle to things like like fert levels. When conditions change the plants have to stop and rewire themselves. Often when plants stunt or leaves go bad, it isnt because theres a problem, its the plant adjusting to the change. What happens is it gives up on the current growth that is wired for the old conditions, and puts its resources to making new growth. Tips stunt and new side stems form, current leaves go bad and new ones come in

So sometimes we just have to be patient and let the plant make new growth. You cant really judge by whats happening to the existing growth, have to wait for the new growth to come in. What you are experiencing may be in large part due to this as well

 

[Koan]

Some plants can handle higher temps, many cannot

Ci said:
Oh, I didn’t know that would be an effect of higher temps.

Ambient heat energy always accelerates all enzymatic processes. Well at least up to their functional limit, then it shuts them down.

Our plants are basically just attractive self perpetuating enzyme factories So yes, they are hungrier now

Looks like the discus sages decree that your anubias, echinodorus and microsorum should all adapt fine. May just be a matter of going all Marie Kondo on your struggling growth as the new leaves slooowly emerge.

I'm sure that your big discus are, ahem, contributing sufficient nitrogen for everyone

 

[Koan]

Dennerle's 2¢:

Discus Aquarium - Dennerle Plants

dennerleplants.com

 

[*Ci*]

Dennerle's 2¢:

Discus Aquarium - Dennerle Plants

dennerleplants.com

Interesting that they don’t include anubias in their list…

 

[Koan]

Interesting that they don’t include anubias

Well and you did mention these are pinto?

It's completely possible the variants may be much less adaptable and less robust or tolerant of extremes then straight up coffeefolia, barteri, or congensis etc.

Buce Plant has everything 20% off this weekend, for Victoria Day and all maybe swap them out with some big new mother pots?

 

[Burr740]

I think most Anubias can be good in the low 80s. Ive seen whites in a discuss tank. Dennerle is likely only including plants they personally offer, rightfully so

 

[*Ci*]

Well, everything you have all said makes sense. I’ve come up with a plan of action based on the suggestions and ideas.

- I don’t think I will replace the plants yet, as the new ones will still have to adapt to my tanks conditions and could have just as much melt as the current ones (it’s not just the pinto anubias - my larger, more common anubias are looking bad, too, as well as the sword and java fern to a lesser degree)

- I will try some slight increase in dosing P04 and K

- I will keep trimming off the damaged and algae covered leaves, maybe even more aggressively.

- I’ll do some checking to make sure my c02 is stable, but I don’t think I will increase it as that will require me to build a new reactor with a longer pipe … unless there is strong consensus that it would help?

- I will be patient and see if things recover over time

Feedback welcome : )

 

[Yugang]

using overflow mode. The bubble escapes maybe once every 2 minutes

So the gas pocket remains clean, and geometry is constant as well.

I run the c02 24/7 so no ramping up time.

This should give optimal stability.

Overall it looks like CO2 must be really good, but a double check always makes sense.

 

[Art]

@*Ci* have you considered dropping the temp to 82F? Still within acceptable range for discus and better for the plants.

I recall, I think George Farmer, did a discus tank where he adapted the discus (slowly) to a lower temp 80-82 and that helped with the plants. I know Heiko Bleher suggests keeping discus always about 75F.