Bubbles .... fish dying one by one

Question
I have white bubbles in patches on the surface of the water in my 20 gallon tank. I used to have 14 fish in there and now i am down to 4. 2 bala sharks, 1 sucki fish grey kind, not the black ones, and 1 tiger barb. Since the white bubbles appeared ( roughly 2 weeks ago ) right after we cleaned our tank, 2 fish died. One was a black mollie, and the other was another barb. I'm wondering what the bubbles are, and if they were the reason of those 2 fish dying. The black mollie, was a hyper fish, and friendly to, ( weird, I know, but he liked anyone by the tank, or when we were feeding he was always at the top, also when my husband cleaned the tank it would swim against his finger ) anyway, the day he died he was acting normal in the morning and by late evening he was already turning grey. That struck me kind of funny. None of our other fish died like that. If you could help me out i'd greatly appreciate it. If there is something i can do to rid the bubbles or anything would be great.

Thanks,
Becky

I wanna save the ones we have cause they are my son's fish ( 5 years ) He really like the bala sharks!!

Answer
Hey :)

Some amount of bubbles on the surface of a fish tank are normal, especially in tanks that have air-driven filters, decorative air stones, or have a hanging power filter and a low water line. If the bubbles are popping regularly and are not covering the entire surface of the tank for long periods, you should not have any long-term problems from this. (Though you should still make sure you are keeping up with your necessary water changes and tank maintenance.)


And sometimes fish can just die randomly and no one will ever no why.

Yours Trully

Chloe xx