Understanding Test Results

[wjaneala]

Just did a full testing:

FC: 5.5
CC: .5 (This one confused me. The water turned clear with one drop. I put the cylinder to the side to do another test, and a couple of minutes later the water was pink again. It took two drops to turn it back clear. What gives???)
TC: 6
TA: 130 (This one also confused me. The water turned clear at 12 drops, then red at 13. So 130?)
CH: 200
pH: 7.8
CYA: 30 (closer to 30 than 40, but about halfway between. So 30?)

So, how's my beast of a pool doing? Anything off? The water looks great!

 

[Divin Dave]

Hi Wendy,
FC is a ppm or so above recommended for CYA of 30. If its 40 you're good. Nothing wrong with being a ppm or so extra though. Lots of us give ourself a little head room.

CC is ok. When you let the test solution sit for 10-15 seconds, it will turn pink again. This goes for teh FC test too. It imporant to test for CC immediately after completing the FC test without any pause. When the solution goes clear, then thats your reading.

TA. You should keep adding drops until the very last drop does not result in any color change or shade of a color change at all, the dont count that last drop. So, if your last drop turned it red, then you should have added at least one more, and if there was no change in the shade of red, then do not count the last drop.

CH of 200 is ok. There is no chemical reaction between vinyl and CH, as long as it dont get crazy high, like more than 500, then you're good.

Your pH is ok for now. You will want to test it every day until you learn how quickly it rises. If you find yourself adding muriatic acid 2 or 3 times a week, then you may want to try and lower the TA to help slow down the pH rise. Thats what TA does...it controls how quick the pH goes up.

CYA is good at either 30 or 30-something. I would call it 30 to be on the safe side.

So, to summarize all of this...I dont see anything wrong! It looks pretty good! Nice job of testing!

Enjoy the pool!

Just did a full testing:

FC: 5.5
CC: .5 (This one confused me. The water turned clear with one drop. I put the cylinder to the side to do another test, and a couple of minutes later the water was pink again. It took two drops to turn it back clear. What gives???)
TC: 6
TA: 130 (This one also confused me. The water turned clear at 12 drops, then red at 13. So 130?)
CH: 200
pH: 7.8
CYA: 30 (closer to 30 than 40, but about halfway between. So 30?)

So, how's my beast of a pool doing? Anything off? The water looks great!

 

[wjaneala]

Thanks Dave!!

 

[Patrick_B]

CC- If this stays clear for 20-30 seconds it's done. If a whole minute or two minutes passes, and it turns pink again, forget it. The test will eventually turn back pink again given enough time. This doesn't count.

TA- If this is red at 13, put in one more drop, and if it does not change any more at all, call it 130. Same rule applies tomCH testing except a Blue endpoint.

Cya-the resolution on this test is 10PPM at best so if it leans to 40, call it 40. Better to dose slightly high than low. How much FC are you losing in the day? If more than 3-4 I would up it to a solid 40-50, but not higher. If you lose less than 3 per day, leave it, but make sure it doesn't slip lower. 40 is a good place to be usually.

 

[wjaneala]

I lose anywhere from 2-4 in a day, depending on the weather. The pool is in full sun from about 8-5:30, and it has been hellishly hot and humid here for a while.

 

[YippeeSkippy]

TA- If this is red at 13, put in one more drop, and if it does not change any more at all, call it 130.

Wendy, just to expand on what Patrick_B said, your test fluid turns red/pink at #12 drops, and if I add another drop of reagent (#13)it turns even *brighter* pink/red.
Since it still changed in that direction I know to add yet *another* drop of reagent (drop #14) to see if that bright pink changes. If it doesn't change again, I ignore that last drop (#14) and call my result 130