Re: Drinking water test kit suggestions?
Simple test: drink the water, see if you get sick. Wait, no, try giving it to some pets or not-so-good-friends first. :-)
If you're reluctant to do that, most municipalities or counties will do water analysis for little or no cost for the residents. If you've got some municipal water supply or county health office, try asking them if that's available to you.
Most of the issues they deal with (toxins, minerals) won't be an issue on a boat but wee critters are probably the only concern. And those can be killed (bleach, UV-C, etc.) pretty much routinely without knowing which ones you've got.