pump question

[mineralrock]

I want to set up a beneath-tank refugium for a reverse photo period. I'm just worried that the return pump will kill off alot of copepods.....is this a fair assumption? And if so are there any alternatives?

[Undertheradar]

this is why many go for the HOB style refugiums that get pumped into and overflow into the tank...they allow the pods safer passage into the main tank.