I finally got my 20g tank cycled (I cycled with fish since I knew nothing about cycling when I set up the tank) about a week ago. Using the API Liquid test kit my values are 0 ammonia 0 nitrite 10 nitrate 8.4 pH (up from 8.2 last week) KH 8 GH 7.5 temp 80 I thought all was going well and was so glad the the cycling process was over, but when I got up this morning one of my platies was dead. He was acting normal last night, as do all of the other fish now. It didn't appear that there was anything obviously wrong when I took him out. I'm sad hes gone but also worried that I might wake up to more dead fish tomorrow. Do you think it could be my pH? I tested my tap water (i couldn't do the 24hr bucket test) and its 8.0-8.2. I'm also wondering if maybe I underfed him because I was so worried about overfeeding! He didn't look skinny or anything when I took him out though. I did a 20% water change and rinsed my filter cartridge. Any other suggestions, interpretations, ideas? Thanks!