Another CYA & Chlorine question

[CarlyK82]

I have a 18 x 48 Intex round blue beauty (LOL) pool. I currently am using the Intex 2500 gph pump, skimmer attached. I have a tube sock filled with stabilizer. But, my problem seems to be that for the life of me I cannot keep chlorine in the pool. I took my pool water to be tested last Saturday at the pool store, where everything was fine except for my CYA was low (at 10). I purchased the container of stabilizer and I put it into the tube sock and hung it on the side of the pool, giving it a squeeze every once and again.

My pool has been looking a wee bit cloudy but I haven't been able to do much with it as we had storms (and of course this had to occur after I vacuumed the pool with my Aqua broom). but today, I went to check the pool and the skimmer is doing its job, collecting what it should. The bottom is going to need a good vacuuming again, but here are my results. I had some test strips so I did both (just cause that is how I am). I used a Taylor K 2000 and I purchased the CYA test to test that, and here are my results:

Strips:
TH = 400
FC = 0
pH = 7.5
TA = 120
CYA = 30-50

Kit Test
TC = 0
FC = 0
CC = 0 (it was completely clear)
CYA = 30 ish (if we had to guesstimate, it would be like 33)

So, my main issue is that even after shocking the pool, I just can't keep chlorine in the dang pool. I have used the pool calculator to figure out what I need to add. So since the FC was at 0, do I just need to start the shock process all over again? I plan on testing my water in another half hour to see what it is currently at (the chlorine levels).

 

[linen]

Get the debris out of the pool and get back up to shock level until:

1. CC is 0.5 or lower;
2. An overnight FC loss test shows a loss of 1.0 ppm or less;
3. And the water is clear.

It will help you greatly if you get a better test kit. See: http://www.troublefreepool.com/pool-school/pool_test_kit_comparison

 

[CarlyK82]

It's what I thought, but I am new to this too, so I am trying to make sure I am doing the right thing.

As far as the test kit goes, I did consider purchasing the K 2006, but instead got the K 2000. I did end up ordering the CYA testing supplies from as well as what I needed for FAS-DPD test as well. I figured (thought actually), those would be the only things I really needed to test.

 

[frogabog]

Are you saying that you have the FAS-DPD kit (r-0870 powder, r-0871, and r-0003)?

If so, an easy fix to your kit would be to buy the TA and CH reagents from TFTestkits. IIRC they're just over $2 each and there are 6 that you need to complete it. Test kit problems solved!

Continue to squish that CYA sock regularly till it is gone. You know how much CYA you've added, correct? Go with that value and don't worry about testing CYA right now. Don't test again for about a week. In about 24 hours after it's gone from the sock, you can assume the amount you added is there and use the appropriate CYA:chlorine ratio for dosing.

I'd be wary of shocking at the minimum CYA level you've tested for while you're waiting for the sock to empty. CYA will rise as it disperses and as such, your shock level will increase silently. I think I'd aim for shocking at the intended CYA level from the get go unless it is over the mustard algae number for your last known CYA (33 right?), just so you don't miss your boat.

Remember, you have to have some chlorine in the pool to be able to measure combined chlorine.