I had a whisper 5/10 gallon filter for a 5.5 gallon tank. I just bought my fish today & I fed him maybe once. I used the betta water purifier thing & set him up with his water and decorations. After maybe 4 hours I went to check on him and I only found a fin in the water. I poured our the filter and he was in there. Shredded. I’m really hurt. Online says the whisper 5/10 gallon filter should be good for bettas. He was probably sucked into the top where the water filters out. Before I even think of replacing him, I need to know if I did anything wrong to prevent another betta dying and this horrible process being repeated. Last time I had a betta I had the litle baby boy and it was in one of the tanks that is automatically set up with filter. He never got sucked in he was much smaller. Different filter but still. Is it possible he was sick? Or did I do something wrong?