30A is probably an overkill, but you have lots of headroom, so it should be good. I lost my first controller do to water seepage. It wasn't a lot of water, but enough. Keep you controller high and put in drip loops. On my 50w panel I use a 10A controller. It works fine and is also a PWM. I am sure since you are only using this to keep you batteries topped off and the bilge pump powered, you will be fine.
Good luck and take some pictures when you are done.
Good luck and take some pictures when you are done.