Hi Kitty;

Just looked at your figures, and your pool data. If you would, test your tap water's hardness. If it's really hard, then draining and refilling won't help the calcium much.

However, draining and refilling are the only way to fix the high CYA. Test your CYA again by mixing your pool water 1:3 with distilled water (Walmart - 1/4 cup pool water; 3/4 cup distilled, and stir, then test). Multiple the result by 4.

Meanwhile, you can fix your algae problem in 3 possible ways:

1. Use polyquat & brush, brush, brush.
2. Use sodium bromide (& brush, brush, brush).
3. Raise your chlorine REALLY high (40+) (& brush, brush, brush).

I'd recommend polyquat + bromide in a small dose + filtering 24/7. I'll put links for bromide & polyquat below. But, you gotta stop using trichlor. Set your tabs aside, for now. If you drain and refill, you can use them. Otherwise, you'll need to give them away. (They don't store well!)
Kem-Tek 60% polyquat @ Amazon
Nava 60% polyquat @ Amazon

Nava Chemicals 652072097 Yellow Algae Remover, 2-Pound Bottle @ Amazon
Tropi Clear TC-4402-1 2-Pound Yellow Eliminator @ Amazon
You can buy locally, but try to find these exact products . . . or be VERY careful, so you don't end up with something that's "just as good", but actually terrible!