My dock started growing these strange domed-shaped gelatinous filled things on it. Are they Bryzoa?

Question

Im on a freshwater lake, the domes are 5inches to a foot in size, and look like they have cells in them... Sort of like a bee hive, but circular not hexagonal. If they are Bryzoa how do you get rid of them? They seem to grow back more if you remove them

Answer 1

Gasoline or bleach..DEAD!!

Answer 2

Yes bryozoans.  They will get bigger than 5 inches.  Why get rid of them?  They are harmless.  But, if you insist, then copper sulfate will do the job.

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