Is this a light issue or a nutrient issue?

[comfycat]

I've noticed some anubias are looking yellow or pale. I'm wondering if I need to start fertilizing or if this is an issue with my lighting?

Tank size: 75 gallon
Inhabitants: 15 Cardinal tetras, 10 green neon tetras, 25 chili rasboras, 10 kuhli loaches, 7 amano shrimp, 6 albino sterbai corys
Lighting: hygger 42w, but I have it dimmed to 25% brightness, and the tank gets an hour or two of sunlight in the mornings. I'm planning to switch to a Fluval Aquasky so it's more customizable.
The tank has been up and running 1.5 years
The nitrates are a bit high at the moment, around 20 ppm, need to do a water change!

I'd appreciate any guidance!

 

[Fishfur]

I've noticed some anubias are looking yellow or pale. I'm wondering if I need to start fertilizing or if this is an issue with my lighting?

Tank size: 75 gallon
Inhabitants: 15 Cardinal tetras, 10 green neon tetras, 25 chili rasboras, 10 kuhli loaches, 7 amano shrimp, 6 albino sterbai corys
Lighting: hygger 42w, but I have it dimmed to 25% brightness, and the tank gets an hour or two of sunlight in the mornings. I'm planning to switch to a Fluval Aquasky so it's more customizable.
The tank has been up and running 1.5 years
The nitrates are a bit high at the moment, around 20 ppm, need to do a water change!

I'd appreciate any guidance!

Is it new leaves that seem yellowed or the oldest ones or most of them?

If it’s the newest leaves that are pale, chances are it’s an iron deficiency. What’s the pH?

Btw, gorgeous tank! I really like what you’ve done with it.

 

[comfycat]

Is it new leaves that seem yellowed or the oldest ones or most of them?

If it’s the newest leaves that are pale, chances are it’s an iron deficiency. What’s the pH?

Btw, gorgeous tank! I really like what you’ve done with it.

Thank you! It's the newer leaves that seem to be affected. I haven't checked the pH recently but last I checked it was around 7.2

 

[Fishfur]

Thank you! It's the newer leaves that seem to be affected. I haven't checked the pH recently but last I checked it was around 7.2

In that case, avoid fertilizer with iron in it that isn’t chelated or uses EDTA as the only chelator.

Look for DPTA or EDDHA chelators instead. Adding some iron should solve the problem.

 

[SeattleRoy]

Hi comfycat

If the issue is the leaves I have highlighted below, and if there are then newer leaves on the rhizomes of the anubias, then I agree with Fishfur that the issue is likely iron related. It could be the result of insufficient iron being dosed, incorrect chelate for the pH of the tank, or excessive phosphate impeding the uptake of iron. Hope this helps! -Roy

 

[3Fishnight]

Have you added any potassium?

 

[comfycat]

Hi comfycat

If the issue is the leaves I have highlighted below, and if there are then newer leaves on the rhizomes of the anubias, then I agree with Fishfur that the issue is likely iron related. It could be the result of insufficient iron being dosed, incorrect chelate for the pH of the tank, or excessive phosphate impeding the uptake of iron. Hope this helps! -Roy
View attachment 917542

Yes, those are some of the pale leaves, though the affected ones look like the newer leaves on the rhizome.

I haven't tested phosphate before. Is it worth testing for, or should I see if the new fertilizer helps? I recently got the Thrive S fertilizer based on recommendations from Fishfur about the type of iron to look for.

Have you added any potassium?

It looks like the Thrive S fertilizer I just got has potassium. I have dosed it just twice so far.

Do you guys have an idea on about how long until I should see improvement if I'm treating it correctly with this new NA Thrive S fertilizer?

 

[3Fishnight]

Yes, those are some of the pale leaves, though the affected ones look like the newer leaves on the rhizome.

I haven't tested phosphate before. Is it worth testing for, or should I see if the new fertilizer helps? I recently got the Thrive S fertilizer based on recommendations from Fishfur about the type of iron to look for.


It looks like the Thrive S fertilizer I just got has potassium. I have dosed it just twice so far.

Do you guys have an idea on about how long until I should see improvement if I'm treating it correctly with this new NA Thrive S fertilizer?

Within a day or 2 or whenever the new growth shows up.

 

[MagnifcentBett]

I've noticed some anubias are looking yellow or pale. I'm wondering if I need to start fertilizing or if this is an issue with my lighting?

Tank size: 75 gallon
Inhabitants: 15 Cardinal tetras, 10 green neon tetras, 25 chili rasboras, 10 kuhli loaches, 7 amano shrimp, 6 albino sterbai corys
Lighting: hygger 42w, but I have it dimmed to 25% brightness, and the tank gets an hour or two of sunlight in the mornings. I'm planning to switch to a Fluval Aquasky so it's more customizable.
The tank has been up and running 1.5 years
The nitrates are a bit high at the moment, around 20 ppm, need to do a water change!

I'd appreciate any guidance!

I don'r have an answer for you. I'm learning from the thread, though, And yout tank is spectacular! Here's my first planted tank. I'm setting up a 16 gallon now and you've given me lots of inspiration.

 

[tinylostwine]

Hi comfycat

If the issue is the leaves I have highlighted below, and if there are then newer leaves on the rhizomes of the anubias, then I agree with Fishfur that the issue is likely iron related. It could be the result of insufficient iron being dosed, incorrect chelate for the pH of the tank, or excessive phosphate impeding the uptake of iron. Hope this helps! -Roy

I would be inclined to believe it is a phosphate issue because in my blackwater aquariums (ph 5ish ec 20 to 40) there is veritually no iron but my anubias never show yellowing problems.

 

[SeattleRoy]

Hi All,

Phosphate deficiency issues typically show up on older leaves, with the following symptoms.
D. Leaf chlorosis is not the dominant symptom. Symptoms appear on older leaves at base of plant.

1. Plant dark green

a. At first, all leaves are dark green and growth is stunted. Purple pigment often develops in older leaves, particularly on the underside of the leaf along the veins...Leaves drop early... phosphorous deficiency

Phosphorus deficiency is not readily identified by visual symptoms alone. Visual symptoms of phosphorus deficiency are not always definite, but many phosphorus deficient plants exhibit off-color green foliage with purple venation, especially on the underside of leaves, and plants are stunted and remain stunted even when fertilizers supplying potassium and nitrogen are applied. Older leaves assume a purple-bronze color. Small growth, especially root development; spindly growth with tips of older leaves often dead. Phosphorus is phloem retranslocated from older leaves to new growth.

 

[SeattleRoy]

Hi comfycat ,
If it is the newer leaves that are showing the interveinal chlorosis (dark leaf veins with lighter areas between the veins) then the issue is likely iron related. It could be the result of not dosing sufficient iron or dosing the incorrect iron ch elate for the pH of your tank. The most common chelate used in fertilizers is EDTA (because it is the cheapest) however it does not work very well if the pH of a tank is 7.0 or higher (aka alkaline). Fishfur is correct. If your pH is 7.0 or higher you want to be dosing DTPA or EDDHA chelated iron in your tank because only 20% of EDTA chelated iron is available to plants at a pH of 7.0 and as the pH goes up higher even less is available. I would suggest using ferrous gluconate (Seachem Iron) or a fertilizer that contains DTPA chelate iron such as Nicocg.com Liquid Iron which contains EDTA, DTPA, and ferrous gluconate. Dose as recommended for at least a month. Watch the NEW leaves as they emerge, do they look greener, healthier? DO NOT WATCH EXISTING LEAVES, THEY WILL NOT CHANGE. Report back on your progress and let us know how things are changing. Hope this helps! -Roy