New to pool ownership and dealing with staining

Jump to latest Follow Reply
T

tbosu

0
Jun 1, 2018
11
St Louis, MO
Hello! We just bought a house with an inground, saltwater, fiberglass pool. It looks like it has years of staining around the waterline that I am currently trying to treat with ascorbic acid. I put about 2 lbs of ascorbic acid in our 10k gal pool last night. The filter has been running continuously but I'm not seeing a huge improvement. Prior to treating it, I took a water sample in to get tested. They said to raise my water above the black stain, add ascorbic acid, and add in some Instant Conditioner because CYA was low. I did everything except add in the Conditioner. I'm not really sure why I should do that now when my chlorine level is 0 for the ascorbic acid. They said I didn't need a sequestering agent because metals are 0.

Before dumping in ascorbic acid:
FAC = 0
Salt = 2800
CH = 300
CYA = 10
TA = 90
PH = 7.5
Copper = 0
Iron = 0
Phosphates = 100

I just tested the PH again and it's still 7.5. How much longer should I give the ascorbic acid? Should I add more and if so--how much is too much? I'm not sure if I should try to treat years of staining all at once or if it's okay wait and try again at the end of the season. I'm just afraid more buildup will occur. Any other ideas? I will take all the help I can get! (These pictures were taken prior to adding water)
IMG_0802.jpgIMG_0803.jpg
 
Hello and welcome! :wave: Well, first thing you will hear us say over & over :blah: is to stay out of the pool store and test your own water with a TF-100 or Taylor K-2006C test kit. That's paramount for proper pool care. Having said that, before jumping to the AA process, did you perform any spot tests to confirm what the black even was? Since you don't seem to have iron or copper in the water, I'm not so sure the AA is going to do anything for you. Have you tried straight bleach, or if you have a chlorine tablet laying around, hold/rub one in an area for a few minutes to look for any changes? I'd be curious to know if that staining is organic. Is it gummy or sticky at all, or does it seem to be embedded?
 
Thanks for the suggestions for water testing kits--I will look into those! We just looked at again this morning. It's not an embedded stain, but more of a hard scaly buildup. Not sticky. The ascorbic acid (or raising the water level) has made it easier to just peel off (like dried glue on your hand) or scrape off with a putty blade so it might just be a day of manually scraping/peeling it all off! Should I put the Instant Conditioner in now to raise CYA levels or wait until I get the water level back down and PH and chlorine adjusted?
 
You can add the conditioner now. It's hot, and your SWG water (FC) needs protection from the sun. Use the PoolMath and go for a CYA goal of 70 and monitor closely for the next 24 hrs. When you increase the CYA, make sure to monitor the FC (SWG table) as noted on the [FC/CYA][/FC/CYA]. That's very important. Your last pH was at 7.5 so that's perfect really. Unless I missed something in your plans today with the water or pool, I think that's about it.
 
Ok, so it's not so easy to peel/scrape off. Maybe it is organic scum. What is the best way to treat/dissolve organic buildup? I have tried Magic Eraser and Soft Scrub without luck. Maybe the buildup is just too thick for those.
 
You could try some 1000-1500 grit wet/dry. Do a small test spot first to ensure you like the results. It's smooth enough to where it should be fine on the gelcoat. My installer recommended grittier paper on mine for other issues. Aside from that, I'm simply thinking routine application of bleach & water with a good nylon brush to eventually cut through the tough, established layers of gum and grime.
 
After scraping off the outer layers with a putty knife we followed it up with the sandpaper you suggested and it removed all the black buildup and most of the white scaling. It looks so much better! Thank you for your help!
 
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply