Cyanuric Acid 200ppm - Drain Pool

[wilburfw]

Pool Volume 16,000/In ground plaster/Inline Chlorinator. I used 32 oz of 6% chlorine yesterday and had Leslie's test water this morning. Of course, they said to drain pool 80% and/or replaster. We've never had these issues before and pool is 14 years old in full TX sun all day. They stated we should only use 1-2 tablets in chlorinator at a time, which may be the issue since we've always filled it and ran it at 4 for 9-10 hours a day.
FAC 0
TAC 0
CH 200
CYA 200
TA 225
pH 7.6
Copper 0
Iron 0
I've heard you can add lye to help lower CYA, is this safe? If we add overnight with pump running will it be OK to swim next day?

 

[topher]

i thought the only way to lower CYA was with water replacement..

 

[loop_pea]

Adding lye will just make your pH go sky high, and then you'll have two problems to deal with not one.

The only way to lower CYA is to drain part of the pool and replace with water that has no CYA.

 

[BigIslandPoolService]

Aloha WilburFW

PLEASE don't add any lye (sodium hydroxide) to your pool... I've never heard of that one...so I think there must be some sort of confusion going on...

I agree with TOPHER and LOOP PEA...you should probably get rid of 3/4 of your pool water and refill it and just balance your water to have about 50 ppm of the CYA, and this will lower your alkalinity too (225 is WAY high for that).

If you have any Caly Hypo shock, you can use that to chlorinate the pool at the start (dissolve it in a 5 gal. bucket over time and just keep pouring off the dissolved water from the top of the bucket), and it will increase your Calcium Hardness (you'll need to raise that after refilling the pool if your water isn't very hard--if you have hard water, you might be just fine!).

Aloha!

 

[wilburfw]

Thanks! Didn't have a warm fuzzy about adding lye. Rather than emptying 3/4 of the pool at once we saw on a website to do a 1/4 at a time and then refill that, and in a few days repeat until appropriate level is reached. We have hard water so, hopefully, we'll be fine on the Calcium Hardiness. Going to try to start using the BBB method.

 

[duraleigh]

You'd better start the drain/refill pretty quickly or get some chlorine in your pool. You will have algae very soon with your FC at zero.

 

[topher]

ive been doing the BBB method since I opened the pool this year. so far my only complaint is the fact I gotta vacuum the pool more often as I can see EVERY speck of dirt on the bottom of the pool and it drives me crazy. - yes it's dirt I live in a farming area there is a field 20` away from my pool and the tractors blow dust into it.
i never had this problem in the past though.. but I guess thats cuz I could only see the bottom fuzzy like.... now I see sparkles on the white spots in my liner.

 

[wilburfw]

Algae was what we thought our original issue was until the CYA came back high. Don't have recommended tester as I just found your sight today. We also live out of the city on two acres and have a "neighbor" building a house on the adjoining property, so lots of dust. We switched from DE to Fiber Clear and have that under control now. Had to backwash more frequently at first due to it picking up smaller particles, but better for us.

 

[Stuamurr]

Problem with just doing 25% drains is its going to take ages to get the CYA level down, first time it will drop to around, 150, second time it will drop by 25%ish again to around 113ppm, then 25% on the third quarter drain to around 85, so that's 12,000 litres put in but only 43.75% of your pool water replaced (roughly)

You need to figure out what your source water will do to the pool, TA/CH/pH, and go from there but with CYA at 200 you definately need to replace at least 50% of your pool water on the first drain to get it down.