Recently switched to a aquaclear 30 for my 20g tank with nano fish. Have to use a sponge on my filter intake tube cause I have small fish. Briefly didn't have a sponge and two celestial pearl danios got sucked up killing one and injuring another. Problem is when the sponge is on the filter goes down to a tiny trickle defeating the purpose of a good filter. Is there something I can use that will protect my fish and shrimp but Also let my filter work to almost full capacity Have sponges on other filters with no problems