I'm leaning toward the Zebras for killing the other fish.....I forgot to mention that after the murderous rampage, the Betta and the Rainbowfish were both hiding and wouldn't come out. They are both very gregarious and always at the front, but they remained hidden and very still until long after the Zebras were gone.
I also neglected to mention that the night before the Zebras had gone schizophrenic. Racing erratically at lighting speed in general and chasing each other. I've had the Betta for a while and she can be a bully, and at the most a fin nipper, but not deadly. And she'd lived with these fish for months, including other fish that really did irritate her. I know they can change though.
And as for filtration. I'm a fanatic about over filtrating and underfeeding. LOL For my 37 gallon in question I have a Penguin 200 and Penguin 150, both with an extra filter and an extra media bag with activated charcoal. I change 10-20% water every 7-10 days. I'm very, very careful with feeding and I feed very slowly and stop at the slightest hint that they are slowing down.
I tried peat in my small Q tank, but I couldn't get the fine peat "dust" to stop coming out of the bag and mucking up my tank. My filter is very small on this tank with no room for a peat bag, so I used a media bag and just hung it in the tank. Messy..... Any suggestions?
I thought about the net chasing ORDEAL too. I wound up ripping just about everything out to get some of the fish, but never did get any of the Black Neon Tetras, 1 Guppy, or the Zebras. Damned fast. Maybe someone sensed the weakness of the Tetras (since they are prone to hysterics) and took advantage. Fish are complicated.
ph is way too high; also your fish count needs to be higher, you need at least 8 zebra danios, 8 tetras, etc. if certain shoal fish are not kept in groups of 8 or more, you will get fin nipping. if the danios and others, but especially the danios and tetras are kept in a group of 8, preferably 10, they tend to chase or play with one another rather than find mischief with other fish. but th eph, anything over 7.4, you are asking for trouble. malaysian driftwood is good. you must soak the wood for several days to get the tannins off. you should avoid chemicals like buffers, go the natural route as best as you can. also, maybe you need to get either a larger tank (the larger the easier to maintain) and/or more water changes; or the worst case scenerio, if a pet shop would take your fish, you can get fish that will tolerate 8.0 ph...hope this helps
