(August 4, 2014 at 10:12 am)Drich Wrote: Massive temp swings can put tropical fish into shock. (Sometimes the recover sometimes they don't.) It is recommended that you transfer fish to a plastic bag/ziplock with the old water and then when the new water is ready put the bag in the new and let it come to the temp of the tank in an hours time. Then transfer the fish keeping the old water out of the new. This should be done any time you take a fish out of one ecosystem and place him in another. (Especially when you bring a new one home for the first time.) also if your going to get serious you might want to get some water test strips.
This is very sound advice. I was going to blame the Beta (too aggressive) until I read they all died after a water change. You might need to add conditioners to the water. The water from your tap/well can have chemicals that are harmful to fish. You really shouldn't change all the water out at once, maybe a 1/3 or 1/4 at a time. As an afterthought, might want to hold off on those tank changes if you live close to Toledo, Ohio!
