First Pool, First Post, Help me get started please!!

[landers16076]

Common story here...Moved into home 3 months ago with a pool that was completed in 2016. Water was and has been crystal clear the entire time along with strong chlorine smell which has now dissipated throughout the winter. Fusion Nature2 Chlorinator has been set on "6", highest setting, since we moved in however I have not added any Trichlor tablets and it is now empty. When tested in the past with a cheaper test kit, chlorine levels were high so I did not add any additional chemicals.

Fast forward to the past few weeks after discovering the TFP website. I have read all the articles in the pool school. Have purchased a Taylor K-2006C test kit and ran all the tests. Here's what I discovered:

FAS/DPD test FCl: 11.4 however when checking combined chlorine, I got nothing
CYA: was very high in fact used only 2ml from vial (a few drops) after mixing and I could no longer see the black dot on bottom of test tube
pH: 8.0
TA: 150
Calcium: 625

My theory is the CYA is high from using the Trichlor tablets which was set on the highest setting for chlorination for who knows how long. The calcium is high because we are on a well and that has also led to minor calcium scaling around the water features.

Question is what is the first step here to getting things going in the right direction and what concerns should I have? Appreciate the guidance anyone may have to offer.

Brock
Ft. Worth, TX

 

[Texas Splash]

Hello Brock and welcome to TFP!

My theory is the CYA is high from using the Trichlor tablets which was set on the highest setting for chlorination for who knows how long. The calcium is high because we are on a well and that has also led to minor calcium scaling around the water features.

CORRECT! You have been reading. :grin: The only way to effectively reduce CYA and CH is a water exchange. To get a better idea of how high the CYA really is, try the dilution test on the TFP Pool School - CYA page start at Step #8. That way you'll know about how much needs to be exchanged.

From there, it gets much easier. Let us know if you have any questions. Nice to have you with us.

 

[woodyp]

Yep.... a partial water drain and fill will fix both of those issues. Welcome.

 

[landers16076]

Yep.... a partial water drain and fill will fix both of those issues. Welcome.

Thanks for the responses. I'll rerun the CYA test to get a better read on the actual level. Instead of draining and filling, is there any harm in waiting until pool season begins and then with the water splashing out of the pool along with subsequent refills, will that bring that CYA level down? Maybe I'm missing the fact that there needs to be a lot more water drained/filled than with just normal use. If that's the case, being on a well with hard water, I'm not solving the high calcium issue so then are we talking trucking water in to refill the pool?

Thanks

 

[cfherrman]

Depends on your cya result and if your pool is green or not.

 

[woodyp]

All that rain we had over the last 10 days or so should've helped some! I got a foot here of CYA/Calcium free falling straight out of the sky. Seems all I did was pump water out.

 

[Texas Splash]

Even a high CH can be somewhat managed by compensating with a lower pH and TA. But when the CYA gets too high, the FC (Free Chlorine) level has to increase to compensate. Eventually it gets to the point where months/years of chlorine tablets and/or stabilized power shocks let the CYA get out of control. Once you do the diluted test, use the Poolmath calculator or even some simple math to get you in the ballpark. For example: Say your diluted CYA test is 100 which means your true CYA is 200. You know that a 50% water exchange will cut the CYA in half. It would take a 75% exchange to get you down to around 70-ish or so. That would take a lot of cannonballs.

Simple fact is the original owners didn't know better and now you have to make it right. Once the water exchange is done, the CYA will not climb unless YOU want it to.

 

[landers16076]

Performed diluted CYA test this afternoon. Estimating my CYA level is at 300. Guess that’s what using Trichlor pucks at the max chlorination rate will do. Calculator shows replacing 87% of the water to bring CYA down to 40.

Question 1: I’ve heard CYA attaches to the sides and bottom of the pool and should be brushed to remove before draining water. True or False?

Question 2: Do I refill with the well water on property and then how do I deal with the hardness issue or have softer water delivered and how much does that usually run?

 

[Texas Splash]

Question 1: Consider this false. Scrubbing the pool surfaces would be most important during a SLAM to remove algae and/or normal weekly maintenance.
Question 2: Normally we recommend avoiding well water because of the iron content. Iron presents a whole set of problems. But if your well is iron-free and the only concern is hardness, then you can do that if you wish. You estimated your hardness a little over 600, and while that is a bit elevated, it's not crazy high. But it's really up to you as to how you replace the water. Definitely avoid iron though if there is any doubt about it in your well.

 

[landers16076]

Great. Thanks for the help today. Tomorrow I’ll try to figure out how to get the water out. I’m sure that will present another round of questions.

 

[Texas Splash]

Oooh, yes. Like me, you have a cartridge filter, so you probably don't have a valve to suck water to waste like those who have sand filters with a multiport valve. If that's the case, you have a couple options ..... several garden hoses and start siphoning, or use/rent a submersible pump. That will pull water out very quickly for you.

Make sure when you do the water exchange, don't get so aggressive that you pull almost all the water out. Always leave about 2 ft in the bottom for structural stability. In addition, don't leave the pebble exposed too long. Make sure once you do the lowering you fill it back up as soon as possible. While a large exchange is more efficient, even if you could only do half at a time before refilling and starting the process again, that's okay.