Marine data on Garmin 330?

 

I recently bought a Garmin 330 Streetpilot and am very happy with it. Is there any way of getting marine maps onto this unit. Everything I can find is incompatible and I'd like to use it for fishing too.

I think BlueChart is

I think BlueChart is compatible with most Garmin units but it's not recommended because the C330 isn't waterproof.
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