First of all,
What size tank do you have.. how many gallons is it?
and
how long have you had your tank set up? And by "set up" I mean with
gravel in it, water in it, filters running, etc.. Chances are, if you haven't had your tank set up for a while, it hasn't 'cycled'...
THIS is the nitrogen cycle they are talking about, please read my friend..
The Nitrogen Cycle
Usually, you start with an empty aquarium, rinse gravel of choice thoroughly, put gravel in tank, add water, add decorations (plastic plants/caves/hiding places etc.), turn on filters and get them running, turn on heater.
Add Stress Zyme into the water according to the directions on the bottle for a new aquarium, then your tank run for about 3 or 4 full days. If you want to make the 'cycle' go faster or establish quicker, scoop a cup of gravel out of an older, already established fish tank with fish living in it, and put it in your new fish tank. or you could take a whole filter from an older already established fish tank and use it for your tank. or just the filter cartridge from an older fish tank's filter and insert it into your filter and use it.
After that, go purchase some tougher, hearty fish such as zebra danios or mollies to further build up
'good' bacteria in your tank. after a few days, check your water with a test kit and see what your
nitrate, nitrite, ammonia, and p.h. levels are. If they are at levels that the kit says is dangerous for the fish, do a 25% water change using a tap water conditioner (such as Stress coat) which removes chlorine from your tap water. Chlorine will kill your fish.
If the levels are within the right ranges that the kit say are fine, you are ready to go buy fish of your choice for your tank.
If the levels are not what they are supposed to be, take the correct measures to make them right.
Talk to a trusted local pet store about what to do to make this happen. Or go buy chemicals to
adjust the levels in your tank until they are right.
Actually here, I found a website..
How To Cycle A New Aquarium
or google "
how to cycle a new aquarium"
Since you have so many fish in your tank already, I'm hoping you HAVE cycled your aquarium and set it up the right way. Or else chances are, you're going to lose all those fish and they'll die.
And you haven't even said exactly what your question is...
The topic says bacterial bloom.
What about a bacterial bloom? What is wrong with your tank?
All you said was Bacterial bloom, and listed the fish that you have.
We need more information.