View Full Version : High TA in fill water
AndyJ
06-09-2010, 09:44 AM
I got a sample of fill water from a friend to test for iron. I ran a full set of tests to see where he would be starting. Here are the results:
pH 7.7
CH 280
TA 400
FC <0.2
CC 0.2
iron 0
All of these seem reasonable to me except TA. I'm wondering if the collection technique or transportation could have a big affect on the quality of the sample. He said he got it from the hose which will be filling the pool, but it was the water just sitting in the hose (he didn't let it run first). Also, I got it in a glass Kerr jar with a 2-part, vacuum-seal type lid (I think it's a standard jelly jar). It was probably in there for at least 10 hours, maybe as much as 24 hours.
Should I ask for another sample, perhaps directly from the spigot? And in a plastic bottle? Or is a TA that high possible from a city water supply?
sturev
06-09-2010, 10:15 AM
Personally I would get a fresh sample! The FC & CC readings are probably not valid (those are very time sensitive). I have high TA in my water also, but found once I got everything up and running and added some acid, it came down and has stayed at a good level.
CarlD
06-09-2010, 10:30 AM
I am much more inclined to doubt the CH and T/A readings than the FC and CC readings. Those may WELL be due to a contaminant in the container. Make sure your container is CLEAN first.
AndyJ
06-09-2010, 10:34 AM
Thanks. I will ask for a new sample taken under more controlled conditions.
AndyJ
06-10-2010, 02:00 PM
Update: did a retest under more controlled circumstances. TA is really 400. Has anyone ever heard of TA this high? I'm wondering if this is something that must be lowered and what the consequences are if he does not.
He mentioned that after shocking he gets a reddish/brown tint which coats his filter cartridge. The red rinses off and he puts it back in. I was assuming that is due to low levels of iron.
Watermom
06-10-2010, 04:32 PM
There is a stickied thread in the alkalinity forum detailing how to lower your alk.
AndyJ
06-10-2010, 06:00 PM
I know how to use acid and aeration to lower TA, thanks to this forum, and I have successfully done that to my own pool. However, I'm not sure my friend will take the time to use that process on his own pool. I'm just wondering what negative effects a TA that high might have if he does not lower it.
AnnaK
06-10-2010, 06:26 PM
That really is very high TA. Is this well water? Or is the water being treated in some way such as through a softener or sanitizer?
aylad
06-10-2010, 07:16 PM
TA that high will help precipitate iron out of water (if it's there) and cause staining. It will also help cause a pool with high calcium levels become milky and impossible to clear up. It also will make pH VERY hard, if not impossible, to adjust. Think of the issues that would happen if, say, his pH were low and he had to add several boxes of Borax to get it raised--that much Borax causes other issues with cloudy water all by itself.
If I'm not mistaken, TA levels also can contribute to scaling problems in high calcium pools, especially those with SWGs.
It needs to come down!!
Janet
AndyJ
06-10-2010, 09:16 PM
It is city water, directly from a hose, not softened or treated at all in the house.
I'll tell him that the TA needs to be treated and point him to the aeration instructions in this forum.
Thanks so much for your advice. I really appreciate it.
chem geek
06-10-2010, 09:21 PM
The saturation index with that high TA is almost +0.8 which is very high and at risk for scaling. Also, the high TA will make the pool have a tendency to rise in pH over time, requiring acid addition (unless Trichlor pucks are being used). You didn't list the CYA level so that could be high and another problem.
AndyJ
06-10-2010, 10:01 PM
Duh, I didn't even think to look at the saturation index. It is a brand new AG pool which he just filled, so there was no CYA. He shocked initially with dichlor, so there is a bit now, maybe 6-10 ppm. The sample he gave me was not large enough to test for CYA after the other tests for TA and FC. I told him to buy a FAS-DPD kit so he can keep on top of his chemicals.
Thanks again for your attention to a newcomer like me. I have been reading this forum avidly for 4 years since I got my pool, so I feel like I know many of you already. I have learned so much from all of you already, but I know there is yet much to learn. It's a privilege to finally be able to register and post here. I hope to eventually be able to contribute as well.