Anyone know what these are?

[Alan_J_MN]

I started seeing a few of these in my sump a while back. At first I thought it was detritus. Now they are all over the rocks in my sump, inside the skimmer and inside the plumbing. I found a few in my tank too, underneath rocks, so they don’t like light.

 

[brmreefer]

Pineapple Sponges

 

[Alan_J_MN]

Thanks! I was worried they might be bad guys. The must have come in with corals - but it is 6 months since I added any new ones. However my nitrates have jumped from consistently less than 5 to 15-20 in the last month or so, which must be why I have an explosion of them.

 

[Cnidoblast]

Not a bad idea if you suddenly have a sea sponge bloom to check your silicon

Sea sponges use silicon compounds in there skeleton

 

[Alan_J_MN]

Not a bad idea if you suddenly have a sea sponge bloom to check your silicon

Sea sponges use silicon compounds in there skeleton

Mid-December, my silicon was 98ug/l (Triton ICP), which I don't think is high. Right now I have a dino outbreak, and I've just ordered SpongExcel to use as part of my eradication strategy

 

[Cnidoblast]

One could plonk some (additive and pigment free) white silica gel beads into the sump if you want to increase silicon - should be slower than adding water glass (spongeexcel)