Like Boris, we use Micron CSC Extra. I have used that on other boats, and it works well in the Gulf of Mexico, on the trailer, in fresh water, and up in the PNW. I do scrub the bottom every couple of months and rarely have to powerwash when we put the boat on the trailer (scrub and rinse). I had the bottom professionally done 5 years ago, put on another coat myself two years ago, and we are due again now. The place that did it for me previously said, "Oh, we can't do that - your boat is too heavy for us to lift." This was just a few days ago, and I reminded the guy that they did it last time. "Yeah, I don't think we should try that, it would be dangerous." I took that to mean: we have plenty of work and don't want to do it. There is another boat yard in our area that (in the past) allows you to work on your own boat there, for a fee. I'll check their price, buy the paint from them, and do it myself if they still allow that.
I find bottom paint is worth the extra effort and expense. We can get critters, fur, and slime on a boat bottom in a couple weeks down here. The ablative stuff makes it easy to remove it, does a good job of keeping the barnacles from sticking.
Best wishes,
Jim B.