Shrimp Fry Clogging my Bilge Drain???

[Gone2long]

I am anchored in the shallows of a large, tropical bay. After being here for about a month, I noticed the bottom getting exceptionally "dirty" . When I cleaned the bottom, I found literally millions of what appeared to be tiny, 2mm long shrimp coating the bottom of the boat. About the same time, my bilge pump started acting up, so I pulled apart the drain and found that it was pretty well clogged.

The bilge drain has a backflow valve on it, down the line from a Rule, Model 24, 360 GPH pump, and the drain exits at a through hull, perhaps two feet above the pump. Before the line makes that climb, however, it has to go over a 6" high beam along the bottom of the hull, which supports the port-side engine mounts. This forms a loop in the line, and, when I checked the line, it appeared that the loop was where the clogging was, not in the valve, since, when I raised the valve to blow into the line, the valve easily fell open. The strange thing however, was that, as the valve opened, I could hear what seemed to be a loud FIZZING sound.

I started huffing an puffing into the line, which thankfully cleared it, but a week or so later, it was clogged again. Could tiny (perhaps even microscopic) shrimp fry have made their way into the bilge, and populated that loop in the line?

Seems pretty bizarre, I know, but I can't imagine what else might be causing the sound and the line to get re-clogged so quickly. Again, there were literally millions of these things attached to the hull.

Has anyone had a similar experience, and if shrimp fry are actually the problem, would putting a bit of Clorox down the drain help solve remedy the situation?

Thanks to all,

G2L