black algae back again

[mack51]

OK I finally got my CYA up to 40 +- and my free chlorine at 13. PH is in good shape. The pool is looking very clear and clean. I still have some black spots lingering. They seem to be oblivious to any chemicals. I'm also using HTC super algae guard (dimethyl Benxyl Ammonium Chloride 30% and Dimethyl ethelbenzyl ammonium chloride 30%. I previously used some copper based algaecide from Leslie's which did absolutely nothing except make my wallet lighter. I had read somewhere in the forums to use Polyquat 60 but couldn't find any. IS this HTH stuff similar in chemical makeup to the Poly?? If this HTH garbage? If so what should I be using? And where can I find it. I'll probably hit it again with the power washer. That should break up the rest of the "black".
Thanks in advance to you all for your insight and wealth of knowledge.
mack51

[PoolDoc]

I'm also using HTC super algae guard (dimethyl Benxyl Ammonium Chloride 30% and Dimethyl ethelbenzyl ammonium chloride)

You are using up a good bit of your chlorine with that stuff -- one destroys the other. If that's your goal, that's a good thing I guess. But if it's not your goal, you're making a mess.

Mack, one of our rules here is we don't mix and match. You don't have to take our advice, but we're not going to spend time answering questions from folks that are trying to a little of this and a little of that. You'd be better off EITHER going with your pool store advice OR with our. Trying to do both wastes your time and ours, and doesn't help your pool.

Good luck!

PoolDoc