Howdy. Long time reader, registering in to ask my first cause I'm a bit stumped.
My tank was setup maybe 8-9 months ago, a 90 gallon.
I have had a pretty good variety of stemmed plants, and a few others. duckweed. some anubais. Java moss/ferns. it all grew like crazy. Some of the stemmed plants I was throwing out buckets and feet of growth a week. My large amazon sword turned from 1 8 inch plant into 10 plants as tall as the aquarium. My tank had a pretty heavy bio load, it had a reasonable amount of fish for the size to begin with, but then I had a large and breeding amount of guppies pushing it really high.
I dose with API leafzone, flourish and use flourish root tabs. Few and far in between, I add a 50gal dose every month or so - I didnt every dose to described cause growth was crazy already.
Then at about 8 months I decided to do a major tank maintenance. The guppies, and a good chuck of fish gone, id' say im down to about 1/2 the amount now. The tank was drained down to the substrate (canister filter), 50% of the plant diversity/mass was taken out, the gravel was vaccumed, etc.
The tank now has 1 large amazon sword, 2 large anubais, 2 large red stemmed leaf plant I cant ID, and alot of Staurogyne repens (maybe 40% floor coverage), 1 small java fern, few small patches of java moss.
I top of the tank with tap water (adding a dose of prime).
After the clean, a few changes were made.
I added a small carbon pack (a 20 gal) to my canister. This was because there was an oily residue on surface of the water after the clean.
I added a large piece of bamboo (1/2 in water, the rest out), note here that this is the only thing that has shown growth since, its growing 3 shoots off its bottom.
I added a few fish to bring my count back up....
2 pleco
5-6 otto cat
3 roseline shark (small)
2 simese algae eater
7 congo tetra
1 kilifish
3-5 various shrimp
3 large snails
lots of MTS and blue ramhorn.
few other random small tetra i missed, less then 4.
I added the glass plates back to the top of the tank (I keep them clean)
I lowered my output nossle. These last two were in an effort to reduce evaporation/extend top up periods.
The residue seemed to be increasing so I removed my carbon and let the tank evaporate until it started to really agitate the water, this cleared the residue (into the water column I understand)
Other strange note; my golden mystery snail who up until then had been crazy active and growing like a monster seems to have all but gone into hibernation, he only comes out every few days for 1 hour at a time, and his shell it turning white.
I'm waiting on a test kit as my got trashed. The lights are 2 56inch LED multicolor strips whos brand is escaping me atm.
So my question is, are there any theories as to what killed my plant growth? Even green hair algae has all but stopped growing? My initial reading made my think a potassium shortage.
Appreciate any thoughts!