Too many sponges and tunicates inside skimmer and HOB filter


New member
Hello guys, I know these guys are normally considered to be an indicator of good reef conditions but is there any drawback of having too many of these guys?

I do not dose any food for filter feeders and only target feed corals but still these guys thrive in any area that is dark and has high flow. As a result there are large populations inside the skimmer and HOB filter. Should I try to remove them or are they beneficial.


New member
There's no such thing as having too many of these things in a tank IMO, although you do need to have a TON of them to make any sort of impact on your parameters. If you've got some extra time on your hands you might want to do a search on "Cryptic Zones."


New member
I think there may be a drawback. After 4 years and 10 months of use, the return lines from the sump to my AGA 75 are significantly impeded by what I believe to be tunicate growth, as is the overflow pipe back to sump. Currently, I am running my return pump back to DT on separate line, but due to clogs in return pipe the most flow I can use is MJ 1200 pump, which is kind of pathetic.

I'm debating whether I should replace plumbing (which may be beyond my capacity to do) or try to clean at least the drain pipe.