I have a 20g tank with 2 gouramis and 7 tiger barbs. The tank came with a 20g filter and i had orderes a 30g filter. I guess the question is should i use both? Thanks.
Might as well use both, HOB filter don't use much electricity anyways. If its too much flow for the fish you can always stick a filter sponge in the output to break up the flow some.