Quick background: I have been wanting to get a fish (singular) for a while, so for my birthday my in laws decided to get me a 10 gallon topfin tank starter kit, set it up, and had it waiting fully stocked for me. My father in law apparently had tropical fish for years so he believes himself to be an expert and said he didn't use any water conditioner because the fish are fine without it. Eek.. The tank has a glofish tetra, two glofish zebra danios, a fancy guppy, and a teensy little guy I forgot to find the name of when I crashed Petsmart foraging for supplies. I desperately need advice. I've had to learn a lot very quickly!! I know the tank is uncycled, a Petsmart employee told me to get a bacteria supplement which I've learned too late isn't ideal after all. I believe that amount of fish is entirely too much for the size of the tank, am I right? They aren't grouping well either. I'm worried about the ammonia levels after learning about cycling, especially since my blue danio has been staying quietly near the very top of the tank and not zipping around like the other danio. I have been doing 10-15% water changes with water conditioner for the past two nights to try to control the ammonia levels, but tonight after I did it all of the fish but the biggest tetra went to the very top and have been hovering there at the surface. I feel horrible and I'm not sure how to help them. The tank is at exactly 78 degrees based my digital thermometer and I match the treated water before drizzling it in. The blue danio already seemed unwell but the others are definitely sick post water change. Should I add more conditioner?? We do have very chlorinated water, but I'm scared to make my poor fish more sick. Or am I changing the water too soon? I'm taking the water to get tested tomorrow morning.