Water Balance After Replaster

[cardude]

I had some plaster issues on my 2 year old pool and the pool company just replastered it while I was on vacation. I had no idea they were going to do it while I was gone, but they did. My pool company is kind of crazy, IMO.

I tested the water this am and got these results:

FC 3.2

TA 120

CH 100

PH 7.0

CYA 0

I spoke with the pool guy briefly on the phone last night and he said to brush the plaster 2x daily and to keep the FC low. I use bleach for chlorine. Any reason to keep the FC low with new plaster?

Is there anything else I should do? The CH looks low according to my Taylor book-- should be at least 150 I think, unless it is different with new pool plaster. I don't want to screw up this new plaster.

Also, how do I get my CYA up to around 70? I live in a very hot sunny climate and don't think the cya of 0 is going to work too well. I have some left over tricholor tabs that would add cya, but can I use those since I'm using bleach?

Thanks for the help!

'

[waterbear]

New plaster is going to cause your pH to be rising as it cures so trichlor is perfect to use right now. For every 10 ppm FC you add with trichlor you will also be adding 6 ppm CYA.Yse the tabs in a floater or feeder (if you have one). When you add bleach just do not pour it in the skimmer if you have a feeder, Take the floater out when you add it and then put it back in about 5 minutes after at the opposite end of the pool. IF you need to get CYA in faster than that just add the required amount or use dichlor, which adds 9 ppm CYA for ever 10 ppm FC added. BTW, how are you getting a reading of of 3.2 for the FC? The only way I know of that actually had that much precision is a Taylor FAS-DPD test with a 25 ml sample. (And if that is the case you do not need that much precision. Use a 10 ml sample. .5 ppm is more than enough precision for a pool.)

If you have new plaster then your CH will rise as the plaster dust comes off (which is why they told you to brush twice a days) It looks like they are doing a standard plaster startup and they added acid to the pool initially to drop the pH farily low, although with a TA of 120 ppm your pH will rise pretty quickly as CO2 gasses off. If you are gong to use bleach you want to normally keep your Ta ar around 80 ppm or even a bit lower and then adjust your CH upward to keep the water balanced but you need to wait unti the plaster is fully cured (and that takes up to a year.)

[cardude]

Yes, I'm using the Taylor FAS-DPD test with the 25ml sample. I guess I'm wasting reagents doing that so I'll switch to the 10ml sample.

Thanks for the advice on the tricholor tabs. I thought they would work well to add the CYA, but I didn't want to blow myself up using both tricholor and bleach. I'll just use the tricholor for now and turn my liquidator off I think.

I'm aerating now since the ph is low and the TA high. Trying to get it to below 100 like you recommended. Not sure if it will work as it normally does with this new plaster throwing things off.

[waterbear]

I'll just use the tricholor for now and turn my liquidator off I think.

Good plan with new plaster, Once the CYA hits its target switch back over. The plaster dust should have slowed down by then. In the mean time brush the pool as much as you can. As far as any other water balance issues, check with the pool company since they are warrantying the work and might have some specific things they want you to do (for example, some want you to use a metal sequestrant for the first year to help prevent scaie deposits and others don't want to to lower the TA below a certain level or put so much acid in a week, , etc). so see how YOUR guys want you to keep it and do it so your warranty stays in effect.