Thanks for allowing me to be part of your forum.
I have had a 9-gallon BiOrb for a number of years and usually just keep 3-5 male guppies. (I recently bought 3 more guppies, so I had 6, but within 2 weeks, 2 died. I just got a water testing kit and have -- GH 180; KH 50ish; pH 6 or 6.5; NO2...