I am hoping to get some advice we are DESPERATE!!!
I have a 20-gallon hex tank. We have had it a little over a year. It was doing well until about December and we started losing fish left and right and I can't figure out why.
For context, we started with 5 Glo Fish Danio, 5 Glo Fish Tetra, and 2 Cory cats. At the moment I have fake plants but I am working on doing some research to start adding live plants.
These are the current tank parameters and they have stayed consistent through this whole ordeal
pH- 7.5 PPM
Nitrates- 5.0 PPM
Nitrite- 0 PPM
Ammonia- 0 PPM
KH-80 PPM (test strip)
GH- 120 PPM (test strip)
Water Temperature (76-78 F)
I noticed our tank turned cloudy and a few days later turned very very green. No algae on the surfaces just green water. The day it turned green we lost our first danio. I did a small water change. It was recommended I limit the lighting. I got a timer after that so the lights stay on for 5 hours daily.
The green cleared but it stayed cloudy. I asked a few people and Facebook groups and it was thought to be a bacterial bloom. I left it alone. There was no change in the water for about a month.
The fish started to die weekly after this all the same way. They would start to swim erratically, then flip around and upside down, and eventually die. This all would happen within a matter of hours with no previous "signs" or "symptoms". I watched one do this in a matter of 20 minutes.
Mid-Jan. we are down several fish and now the water is turning green again. I broke down and treated the water with API Algeafix and accu-clear. This finally gives me clear water....for a few days. Then we were cloudy again.
So here we are end of Feb. I have 1 glo fish tetra, 1 danio, and 1 cory left. I did a water change again over the weekend due to the worst green water I have ever seen.
Anytime I do a water change I use conditioned water and then dose with seachem stability. I don't change filter media, I have sponges and just rinse them in fish water.
If you read this far I appreciate it. I just wanted to encompass the WHOLE story.
What am I doing wrong????
The attached picture is of the tank last week and that is generally how it usually looks.