Single mom 18000 gallon, de filter chlorine pool w hot tub- old school plaster

Bought the Leslies brand $49 DBD Total Poolcare Taylor test kit today and here's my stats: TCL 1 Br 2, PH 7.5 ppm, Total Alch 70 ppm, Calcium hardness 90. Cynamuric Acid 0. I added 8% bleach and brought tcl up to 2-4 for tonight. My question relates to the lack of any stabilizer in the test. My sample was completely clear and I could see the black dot in the bottom clearly even at the top of the fill. I guess that means I need cynamuric so my chlorine will not leech out. Should I buy the Leslies powder cynamuric acid and how much should I add to be safe to my 18000 gallon pool? (I don't get the corrective add stuff portion on the back of the instructions )I've had reoccurring black algea, green and slime for years so I assume it's because there's never been a consistent amount of chlorine in it due to Houston's hot sun. I'm ready to convert to the BBB method and done using Leslies Black Algea Killer for the slime that inevitably appears. I've been my own pool guy for a couple of years now and need to stop dumping cash into this awesome pool!

What have you been using for your source of chlorine before you added the bleach? Please give ingredients if you can and not just product names.

A CYA reading less than 30 won't register on the test. You do need to add some CYA but you have to go slow and assume that your reading is nearly 30 when you plan how much to add. Otherwise, you may get the level too high. I'm going to suggest that you start out by adding 2 lbs. That should add an additional 15ppm or so. Once it has had time to fully dissolve, we'll have you retest it and then see where you are before advising that you add more. When you buy it, just make sure it only has cyanuric (or isocyanuric) acid in it and not other things blended in.

You can put the CYA powder in an old sock and hang it in front of a return jet. Give it a squeeze every now and then to help it dissolve. A week later, retest your level and report here and we'll help you decide if you need to add more or not.

In the meantime, test your chlorine and pH each evening. Add enough bleach to take your chlorine level back up to 5 or 6ppm. For reference, in an 18K gallon pool, each quart of 8.25% bleach will add about 1ppm of chlorine and each of the 121-oz jugs will add about 4ppm. Those numbers can help you figure out how much bleach to add when you test. Best to test and add bleach in the evenings, by the way.

With a plaster pool, you actually want your calcium hardness reading to be between 200-400ppm. So, you might want to see if you can find some cal-hypo and use that for awhile to build up your calcium level.

By the way, you can ignore the bromine column on the tester since you have a chlorine pool. You might want to consider buying an add-on kit to use with your DPD kit. DPD testers can only read chlorine levels up to 5ppm. You really need the ability to test levels higher than that in the event that you do get algae and need to shock. If you pick up the Taylor K1515, it will give you the one test that your test kit is missing that can do that. You probably won't find it locally, but can get it through this link:> http://pool9.net/tk/

How does your water look now? Any algae?

Hope this helps and welcome to the Pool Forum!

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I'd like to add that the FAS-DPD test is far easier to read especially for Combine Chlorine.

Thank you Watermom!! I've been using granulated Calcium Hypochlorite hydrated oxidizer to shock. It says it's 73% calc hypo and 27% Other. The chlorine tabs are 99% Trichloroethane-s-triazinetrione and 1% Other. Available chlorine is 90% in the 3" tabs.

Currently the chlorine is at a 2 and ph 7.5. I added about 50 oz of the 8.25% bleach last night and my last three chlorine tabs. I plan to buy the CYA Powder and cal-hypo today and will test again this evening. How should I add the 2lbs of cya? Broadcast it or put it in the skimmer? Also, is there a clever way to hang the sock over the ledge and return jet? Stocking holder maybe?

My water looks beautiful and clear today. I think it's the bleach I'm adding daily. There's not any visible algea but a slimy feeling in the stair crevices. I think I'll try to shock with the bleach after I add the cya and hypo calc. Will report back after testing tonight

You guys are Awesome!

Thanks Watermom and BigDave!

The shock I've been using is a granular 73% Calcium Hypochlorite hydrated oxydizer. The label states 27% "other". I use 3" chlorine tabs called Trichlora-s-triazinetriene 99% They are 90% chlorine.

I plan to buy the CYA and cal-hypo for hardness today. Should I broadcast the 2 lbs of CYA or add it in the skimmer?

The water looks beautiful and super clear now. I think its the result of adding bleach everyday. There's no visible algae but it feels slimy between the stair creases.

It's probably time to shock it and I was thinking of using an overdose of bleach instead of the granular calcium hydrochlorite. I'll post test results after the CYA has dissolved.

You guys are awesome!

You can just use some string to wrap around the sock and then wrap the string around the top edge of the pool or use some duct tape or something. Or, just pour it slowly into the skimmer while the pump is running and then keep your pump running 24/7 for 4 or 5 days after you add it and don't backwash during this time. About a week after you add it, run the CYA test again and report your number.

Glad the water looks good. Hopefully, we can help you keep it that way! ;)

@Watermom: OP has a DE filter. Do you recommend adding CYA in skimmer with a DE filter?

Better to put it in a sock in front of a return.