I have cory fish that have been spawning for weeks. My other fish kept eating them before they could hatch. So I set up a nursery (2 gal) tank. I put the cory fish in there and I have eggs. My question is: Will an under water filtration system in the 2 gal. tank be beneficial or harmful to the new fry when they hatch? Should I disconnect the filtration system and just leave the bubbler in there? Please advise.