I have lost three guppies in three days. The first one was a male and I had no idea why he died, I never saw him sick. I found a baby guppy after that alive. I then lost my very pregant female who start acting like she had swim bladder disease--she was swimming with her head pointing down. Then I lost a red tail male today. He was doing the same thing except he was swimming with his head pointing up. All three of them showed no other symptoms. I did a salt bath for the last guppy and he seem to rally but died anyway this morning. I have 2 corycats, 1 neon, 1 baby fry guppy in a breeding net, and 5 more guppies one of whom is very, pregant. The newest fish is over a month old. I put melafix in the water and I have added salt and are continuing to add more after doing a 25% water change this am. The PH is 7.0, temp is 76-78, Amonnia is 0 and I was told my nitrates were trace but not a problem in a 10 gallon tank. I have fed all flake food using the one that allows you to dial up to four different types of food. I added some chopped lettuce this am but no one is eating it. Should I treat the whole tank with Jungle Elimnator? I have that on hand and read it can cure swim bladder or do I wait for more to get sick? How much H20 change to get the one dose of Melafix out and will this hurt the baby? I have no other place to put the baby at this time. Thank you.