Thank you for this forum. I've learned a lot in reading the posts, but have some questions now. I'll start by saying this pool is old and badly needs to be re-plastered. There are pit marks and rough patches all over the pool that harbor algae (probably 30 altogether). To make matters worse, I let it get very bad (think swamp, tadpoles this year) during the off season every year and have to do massive amounts of work to get it blue and clear. But I have restored it every year (year 9 at this house) with help from the pool store and youtube. That was before I found this site which seems to stress only using chlorine, acid, stabilizer, filtration, elbow grease and time. I ordered the TF-100, but it did not come in time so I am kind of slamming blink right now. But I had to use the 3 day weekend to get started. It actually looks good right now.
Yesterday (see pic below) I added about 1/2 gallon of acid which brought the swamp ph to about 6.8-7.0 (I may have added too much) Then I started slamming with 5 gallons of chlorine with no filter (my old filters maxed out the pressure). Two hours later, I brushed it and added 5 more gallons of chlorine. It was foaming and starting to turn blue and cloudy. I skimmed out the dead tadpoles.
I went to the pool store to buy a new filter and get the water tested. I told them about the advice on this site, but they still pushed algaecides which I bought (but am returning today). Their test measured:
5.0 ppm FC chlorine
5.0 ppm Total chlorine
8.0 pH (which I've read is not accurate during a SLAM)
130 ppm total alkalinity
200 ppm calcium
40 ppm stabilizer
I went home, added two more gallons of chlorine and ran the pump all night with a brand new filter (pressure was 12 with the new filter). This morning, the pressure was 22 and the pool looked blue (see pic below). I cleaned it with a aquacomb thingy and put it back in. The pressure was 12 again. I poured 2 more jigs of chlorine in (20 gallons total by this point) and went to church. When I got home, the pressure was back at 22 and the jets were barely moving. I cleaned it a 2nd time. But the pressure was at 20 as soon as I put it back in. So, I'm wondering if this process is killing the brand new filter. My idea at first was to use floc to drop the solids and vacuum to waste into the yard to save the new filter, but I didn't do that because this floc seems to be a no-no here. I guess at this point, I'm wondering if I should use floc and vacuum or keep cleaning the filter every two hours. Thanks for any tips you can offer.
15,000 gal. plaster pool
Hayward C1200 filter
Hayward 1HP pump