First numbers with TF100

[dravenone]

Hi all, got my TF100 and was hoping to get some thoughts on my numbers and what I should fix first, second, etc.

FC 9.5
CC 0.5
PH 7.2
T/A 130
CH 1,200
CYA 100+ (never reached a line on the tube)

Some background;
Before my TF100 arrived I had an algae bloom (grren algae but could see bottom of pool no problem) and used the granuals I had to raise the chlorine level to kill it. I also have 2 floaters each filled with 4 pucks that I have not yet removed from the pool. I have read, re-read and read again the pool school and am now comfortable to switch to bleach until I install my swg, I have several adjustments I need to make to get in balance and am wondering what I should adjust first, second, third, etc.

Also I'm not very confident my CYA level is right due to the water temp (too cold?). I don't have a number on my water temp (So Cal area). CYA was the last test I did, but I'm not sure the few minutes I took to do the other tests was enough time for the water to reach room temp.

My water is clear, I do see a "scum line" in places where the water meets the tile and there is no more algae. If it matters my tap water CH tests at 200. Thanks and I hope I provided enough info.

 

[JasonLion]

Both your CH and CYA levels are extremely high. You really need to get both of those levels down significantly. Fixing either of them requires that you replace a large percentage of your water, probably something like 75% minimum and preferably more.

When doing large water replacements, you want to think about how deep the local water table is likely to be. If it has been dry and your land is well drained then you will probably be fine. But if it has been raining a lot recently or your land tends to be wet or swampy you don't want to replace too much water at one time.

 

[dravenone]

Thanks Jason, I'll start first with water replacement. We're in a bit of a drought and I'm feeling a bit guilty about changing so much water. Is there a CH level that though still high would be maintainable? If the 75% change is best for now and in the future I will do it.

It's pretty dry where I am, I actually drained last year because it got out of control, and now I understand why, and my pool didn't pop out of the ground so I should be good with 75% drain if needed.

Thanks for your help!

 

[JasonLion]

You could probably get by this season with a 50% water replacement, though that partly depends on just how high your CYA level really is. However, your CH level will continue to go up. A smaller water replacement now will mean replacing water again sooner than if you do a more complete water replacement right now. A 50% water replacement will get your CH level down to 700, while a 75% replacement will get it down to 400. In the long run, more frequent small water replacements use more total water than less frequent large water replacements.

 

[JohnT]

Is there a CH level that though still high would be maintainable? If the 75% change is best for now and in the future I will do it.

It would help if you'd add your general location to your profile because some areas are known for high CH in tap water. In parts of Arizona there is a service available to remove calcium from pool water.

You should also know that the CYA test is not as accurate at high levels. Yours could be 200 or more ppm. It might benefit you to dilute a pool water sample 50-50 with distilled water and retest the CYA to get a rough idea of how high it really is. That way you'd have all of the information you'd need to make a drain decision.

How much water did you drain last year? I'd be surprised if your CH got to 1200 in just a year from evaporation and replacement since your fill water is only 200ppm, so I'm concerned that your pool has spent some time at fairly low pH where it was removing calcium from the plaster.

 

[dravenone]

Thanks JohnT,

When I looked back it turns out I drained and filled 100% in 2007. I'm in Southern California, Los Angeles area to narrow down a bit more. My CH may be a bit lower , after having done more reading I was not swirling and giving 20 -30 seconds for each added drop to do its thing. I will re run that test hopefully tonight.

Also thanks for the tip on the CYA test, I will re-run that one as well.