Trying to figure out if I have deficiency
Recently my tank has been decimated with BGA and I'm still trying to figure out the root cause of it. So one of the causes could be an imbalance in my fertilizing.
It's a 20 gallon with 2x 24 watt T5-HO 6500k lights and has 1 inch of dirt capped with sand and is 3 and half years old or so.
It was quite heavily planted (overgrown) but algae took care of that! I dose with APi leaf zone and Flourish comp based on what the bottle says and also have red sea DIY Co2 running and dose with api co2 booster/excel. And used to (just haven't been able to find them for some reason) add the flourish root tabs next to the plants that needed it (crypts, swords).
I've used this setup for quite a while and all the plants grew fine and fast. The Rotala took over the tank, the dwarf sag carpeted, and my anubias barteri grew up and out of the water. And throughout that time I never had an algae attack or anything bad happen.
Though, my crypts would and do sometimes get a few holes in there leaves or their edges are sorta eaten away like a caterpillars been chewing at it, and my dwarf sag does sometimes like to do massive die offs where the leaves turn translucent and spread forming a small circle of death. But it always recovers.
As of now the crypts are showing holes in their leaves, the dwarf sag is dying off, and even some leaves on my anubias are getting a hole or two in them and I have BGA. So something must be off.
Any ideas as to what I might need to add or is missing?
I thought I had a good balance but something has to be missing. I was thinking maybe NO3, since that's what causes BGA, but the plants don't seem to show any signs of that...
I was also thinking potassium, but I'm pretty sure that's covered by the Api leaf zone. And I know that before If I missed a few weeks of dosing the APi leaf zone, my rotala would get holes in their leaves, and yet the ones that remain have none.
Here are some crappy pics. Showing the hole in my anubias (a new leaf has since grown straight through it) and the holes and weird edges of my crypts, and also in the same pic you can kinda see the dwarf sag dying off.