Surfergirl

Sep 11, 2013
6
Hello everyone:

I have been reading a great deal on this site, and just barely started slamming my pool.

Here are my pool specs:

about 28,000 gallons
IG plaster
date: 1984
cartridge filter, 520 sq ft, 150 gal/min, model # CCP520 Pentair
Pump 2HP 2speed
heater mastertemp 400 Pentair
spa
dolphin deluxe 4

My test results:

FC; .5ppm
CC; 1ppm
pH; 7.5
TA; 70-80
CH; 550
CYA; 30


My water is very clear.

We started maintaining our pool ourselves in May, taking over for a pool maintenance company. We have had algae very frequently each summer (this is the third summer of owning our home/pool) and decided to take matters into our own hands. We live in Houston, and so maintain the pool year round. We found our filters were filthy, even though the pool company said they had been cleaned. We replaced all four filters, and using lots of Power Powder Plus, took care of the algae, or so it seemed. Ever since we began caring for our pool in May, our FC levels have been almost zero or near zero. Three or four weeks ago, we noticed spots like moles on the bottom of the pool, which we guessed are black algae. They scrape off. We had a few spots on the steps the whole time we have lived here, but nothing spread until recently.

My questions are:

Is my target shock level 12, or does it need to be a lot higher like the shock level for mustard algae?

Could I get some information about getting rid of black algae?

I have scraped spots off with a chlorine puck, and we even rented scuba equipment and went after spots on the bottom with a stiff nylon brush...How much of this is necessary to eliminate it?

Thank you very much,

Vickie