Another CYA question

[jwalkermed]

I have a new pebble plaster pool. Was plastered 10 days ago. Not much real direction from my PB. He did an acid start up I believe. I've taken over and am managing the pH with acid additions to keep the pH in range on this newly plastered pool. I know I need to add Chlorine now.

I'm going to use trichor pucks for now ( I know that's frowned apon ). Would it be better for add CYA to get the level to say 30, add enough bleach to get FC in right range and then go with pucks or just start off with pucks knowing eventually the CYA will rise.

With the second method I suppose I't be hard to get the FC to right level with no stabilizer on board at first.

I'm hoping w/ back washing the filter and adding water due to evaporation I can keep CYA in check.

I have a k-2006 test kit btw.

Cheers

 

[JoyfulNoise]

You can use trichlor pucks initially to raise your CYA and keep a constant dose of FC in the water but it is a slow process. Each 3" puck weights roughly 8oz so you can determine using PoolMath how much CYA that adds. Every 10ppm FC added by trichlor adds 6ppm of CYA. The added benefit of using trichlor pucks during the early plaster phase (when curing is still happening) is that the acidity of the trichlor helps to keep the pH rise down.

You can certainly raise your CYA up to the minimum level (20-30ppm) using granular stabilizer and then let the trichlor take you up to your final value. Then just make sure you fine tune your FC using bleach and switch exclusively to bleach once you've reached your target CYA level. Trying to manage a pool's CYA by using stabilized chlorine products (dichlor and trichlor) and water exchanges is certainly an option but it is often a more expensive approach than properly chlorinating your pool with liquid chlorine/belach.

Please add more details about your pool to your signature and folks here can be a lot more helpful. Few people probably know which part of the country Boerne is in and our advice varies sometimes depending on where you live exactly.

And FYI, we don't "frown upon" the use of any chemical. We simply strive to teach our members to know what the chemicals are, what they do to your pool water and to only add to your pool that which it absolutely needs. Our goal is to empower our members to know how to manage their own pools and save lots of $$$ in the process.

 

[atttech-2]

I'm hoping w/ back washing the filter and adding water due to evaporation I can keep CYA in check.
Cheers

CYA does not evaporate with the water. The water goes the CYA stays , same for CH.

 

[jwalkermed]

CYA does not evaporate with the water. The water goes the CYA stays , same for CH.

True but if I replace with fill water it will dilute the CYA. Maybe not enough to matter. I don't know yet.

 

[JoyfulNoise]

True but if I replace with fill water it will dilute the CYA. Maybe not enough to matter. I don't know yet.

CYA is only diluted when pool water is removed (backwashing, splash out or rain overflow) and diluted with fresh fill water.

Replacing water that has evaporated does nothing to reduce CYA.

Typically, backwashing and splash out volumes are too small to be of any significance. In my own pool, an inch of water replacement is only ~1% of the total volume but represents close to 300 gallons of water or a 3-1/2 minute backwash. I never backwash that much water.

 

[jwalkermed]

CYA is only diluted when pool water is removed (backwashing, splash out or rain overflow) and diluted with fresh fill water.

Replacing water that has evaporated does nothing to reduce CYA.

Typically, backwashing and splash out volumes are too small to be of any significance. In my own pool, an inch of water replacement is only ~1% of the total volume but represents close to 300 gallons of water or a 3-1/2 minute backwash. I never backwash that much water.

Yeah I'm wrong sorry. thanks.

 

[Texas Splash]

JW, welcome to TFP! Sounds like you're in the traditional start-up phase of your pool by now. While it's important you follow the PB's start-up recommendations (if they gave you any), you might like to refer to the TFP Pool School - Start-up New Plaster page as well just to see if what you are doing is similar, or if they omitted something. Naturally, keep lots of acid handy for the frequent pH rises. Today's weather should have given you some fresh water. Congrats on your new pool.