How bad is this?

[timemachine]

bought boat last fall. Noticed this in filter on one engine. Is it debris or growth? How do I clean it out?

 

[NotHerDecision]

I really need a couple more pictures. Looks like algae to me. You need to follow frank Webster’s fuel management protocol. Use the biocide in shock treatment quantities then change your racors. Once you have clean racors then disassemble the filter bowl and clean it and reassemble. The rebuild kit for the racors is inexpensive and takes about 30 minutes to an hour. Definitely don’t ignore it