Canister filter blockage

[kwan]

Last week the return flow from my external canister had significantly reduced. So I opened up my canister to see what the blockage was. What I found was hundreds of white jelly like beads clogged up the filter material and on the side walls and passage of the canister. They don't move or anything like that, and can be removed quite easily. The question is what are they??

I also notice there are a few attached to my PH intake guard which I have left alone.

[vega]

Either egg or fish food that covered by fungus.