I have a clown loach that is lethargic compared to its normal level of activity. I had a loach die last week that I thought was due to damage from high nitrite levels. I have had a rainbow fish and a bamboo shrimp die this week. Water conditions: Amm: 0 Nitrite: 0 Nitrate:0 after recent water change ph: 8.0 (i need help with this too) kh is high gh is low (I use the liquid test kit and am out of the strips) 20 gal long tank with live plants and 2 cave like areas made by flat rocks on holes in the sand. i use a aqua clear 30, a uv water sterilizer for a couple of hours a day, a tretra whisper 30, 1x1x1 airstone. 2 weeks ago I had a huge ammonia spike that turned to a huge nitrite spike, but is now normal. Yesterday i found a dead bamboo shrimp and my rainbow fish was dead. My rainbow fish was new and I have never seen it eat. My loach is very thin and laying on its side on the bottom of the tank. Yesterday it was fine and eating like a pig. its gills are very red. Please help.