Puffers acting sick
I started off with three dwarf puffers in my tank. One of the puffers became very emaciated after a few weeks, so I thought he might have a parasite, but he died before I could get any medicine for him. I tried soaking his food in garlic in the meantime, but that didn't work. Now my other two puffers who were behaving normally are acting strange. One hangs out at near the surface of the water just floating around. He'll still get excited for food, but is a little thin. My other one sits near the bottom and doesn't get excited to see me like he used to. He's nice and plump, though. Water is fine. pH: 7.2-7.6, ammonia: 0, nitrites:0, and nitrates: very near 0. Anybody know what the problem could be?