First of all I’d like to say this site is fantastic. As of last year I’m a new pool owner and I have found the site to be invaluable during all phases of pool planning, construction and maintenance.
The construction for our concrete 18 X 36 pool began late in the fall of 2013 and it opened in May 2014. Now that we’re into our second season we’ve discovered some spots on the floor of the pool that resemble brown and black sand. The pool has a standard white plaster finish. The surface of the plaster underwater is noticeably less smooth as compared to the plaster just above the waterline. There is also some modest amounts of marks on the floor of the pool that (the company that company that opened the pool) referred to as crocodile skin.
I brought the situation to the attention of my pool builder and he said he believed the pool had a bit of calcium build up. He suggested adding 10 gallons of acid, turning off the equipment for 3 to 4 days and to brush for 3-4 times a day. He said that should break that calcium up. He said that once it feels smooth I could add alkalinity increaser to balance the water again. He suggested having the water professionally tested afterward. He also said this problem could have been caused by high PH over the winter (we closed our pool in early November of last year). He forewarned me of this so (as he suggested) I pulled back the cover in mid-January and added one gallon of acid then brushed the entire pool for 30 minutes. I had hoped to repeat this process but never made the time to do so. Last season, during the beginning of the curing process, I was very good about checking the PH every week and adding acid as needed in order to keep the PH from skyrocketing (I’m happy to say the PH fluctuation has finally slowed down here of late).
I’d truly appreciate a second opinion on this problem before I make such a drastic change. I should add that our children (of course) have already been in the (very cold) pool for several swims this year but have not complained of a rough pool surface. I’ve been very diligent with the pool testing (last year and this year) using the TF-100 test kit which has been extremely helpful. Below I’ve included an underwater photo of the problem and some recent test results. Thank you!
5/18/15
FC 4.5
PH 7.8
TA 50
CH 400
CYA 50
Salt 3800
4/24/15
FC 6.5
PH 7.2
Salt 2800
4/17/15 (pool opening)
FC 0.5
CYA 70
Salt 2600
12/27/14 (before adding acid)
PH > 8.2
8/27/14 (towards the end of last season)
FC 4.0
PH 8.2
TA 80
CH 325
CYA 50
Salt 3200
The construction for our concrete 18 X 36 pool began late in the fall of 2013 and it opened in May 2014. Now that we’re into our second season we’ve discovered some spots on the floor of the pool that resemble brown and black sand. The pool has a standard white plaster finish. The surface of the plaster underwater is noticeably less smooth as compared to the plaster just above the waterline. There is also some modest amounts of marks on the floor of the pool that (the company that company that opened the pool) referred to as crocodile skin.
I brought the situation to the attention of my pool builder and he said he believed the pool had a bit of calcium build up. He suggested adding 10 gallons of acid, turning off the equipment for 3 to 4 days and to brush for 3-4 times a day. He said that should break that calcium up. He said that once it feels smooth I could add alkalinity increaser to balance the water again. He suggested having the water professionally tested afterward. He also said this problem could have been caused by high PH over the winter (we closed our pool in early November of last year). He forewarned me of this so (as he suggested) I pulled back the cover in mid-January and added one gallon of acid then brushed the entire pool for 30 minutes. I had hoped to repeat this process but never made the time to do so. Last season, during the beginning of the curing process, I was very good about checking the PH every week and adding acid as needed in order to keep the PH from skyrocketing (I’m happy to say the PH fluctuation has finally slowed down here of late).
I’d truly appreciate a second opinion on this problem before I make such a drastic change. I should add that our children (of course) have already been in the (very cold) pool for several swims this year but have not complained of a rough pool surface. I’ve been very diligent with the pool testing (last year and this year) using the TF-100 test kit which has been extremely helpful. Below I’ve included an underwater photo of the problem and some recent test results. Thank you!
5/18/15
FC 4.5
PH 7.8
TA 50
CH 400
CYA 50
Salt 3800
4/24/15
FC 6.5
PH 7.2
Salt 2800
4/17/15 (pool opening)
FC 0.5
CYA 70
Salt 2600
12/27/14 (before adding acid)
PH > 8.2
8/27/14 (towards the end of last season)
FC 4.0
PH 8.2
TA 80
CH 325
CYA 50
Salt 3200