Some are against using vinegar, some are not. I'm not planning on ever using vinegar to clean my loop. Instead when the time comes (in a few months probably), I'll simply drain it, disassemble it and use hot demineralised water for the rads and open up the blocks to see how they are faring.
If you're using flex tubing you might want to consider replacing it depending on how much of a film they have developed inside of the tube.
I'm using a hardline loop so that's all I'll be doing for my loop.