"Dirty" looking pool bottom.

[dolfinfin]

Hello all,
I've been spending quite a bit of time reading the forums here and am truly amazed at how much information there is. I am the proud owner of a new home and pool that I had built from a dirt lot. The pool had a very difficult start-up and was cloudy after the initial fill in January for well over 2 weeks. Shasta was my pool builder and had various guys come by and dump this and that in the pool and EVENTUALLY they were able to get the thing clear so that I would sign off on the paperwork. During this whole time I was executing the start-up procedure to the best of my ability..... brushing the pool every day and running the pump 24/7. Given that I couldn't see the bottom through the most critical part of the startup, the ended up being quite a bit of buildup on the bottom that attracted all of the dirt that invariably got blown into the pool due to new home construction around me as well as my own yard landscaping being put in. Fast forward 6 months till now. I was on the "pool store" support path for the first few months... buying and adding what they said I needed to keep the numbers balanced, but really did nothing aside from adding acid from time to time and keeping chlorine tabs in the hopper. Just a few days ago I noticed a black mark near the deep end of the pool. I pretty much knew what I was in for since I had been running low levels of chlorine for quite some time. It continued to bloom. Last night I tested at 7.4 ph, .8 FCL, and 1.7 TCL and proceeded to dump (8) 121oz bottles of 8.25% bleach into the pool in a bid to get up to a FCL of somewhere in the range of 30. I neglected to test my CYA levels, but I know they are NOT high... so hopefully the shock is successful. BTW, I have a LaMotte ColorQ Pro 11 tester.

Back to the real reason for my post... I have what I would assume to be buildup from when the plaster was settling on the bottom of my pool. I read a thread here about Ascorbic acid/Citric acid as being a possible solution to get the bottom of my pool clean. I had a guy out fixing a leak in the pool equipment and he had just a handful of grains of "Jacks Magic" "step 2 copper and scale stuff" remover. We tested what little he had in a small area and it seemed to pull the dirt up and clean quite well. My real issue is that I'm not sure 1) if this stuff is the right stuff for my situation (calcium + dirt as opposed to metal stains), and 2) how I fit a cleaning cycle in to my current attack on the green monster in my pool. If you made it this far, THANK YOU. I appreciate you folks and hope that over time I can become a contributor as I learn from my mistakes that I have and invariably will make as I transition to a BBB method for keeping my pool clean.

 

[Texas Splash]

Hello and welcome! Okay, I made it. Woo! Now on to some help to get you going:
1 - I'll say this now to get it out of the way ….. While the LaMotte is better than nothing at all, and certainly better than free testing or test strips, it's not a TF-100 or Taylor K-2006C test kit which is what we recommend. I just had to get that out now since others will probably wonder. :blah:
2 - Organic staining (algae) happens when the FC and CYA are not balanced in accordance with the [FC/CYA][/FC/CYA]. Too low a CYA and the sun eats your chlorine. Too much CYA (common from lots of tabs) and the FC can't keep up. So that chart is important.
3 - Plaster warranty. Is there one? You might check with your builder. Now if they "cut the cord" and you're on your own, then by all means make sure to balance everything IAW our Recommended Levels page (link below).
4 - You know pH rises quick with new plaster, so watch that one closely to avoid scale issues. Keep pH around 7.5-7.6 if you can.
5 - Before you go crazy with too many treatments and products for the staining or anything else, I'd get all the levels fixed first. Everything you need to do that is in my signature below. Make sure to use that PoolMath tool. It does the measuring for you!
6 - For the stained area, try this approach:
-- Rub a chlorine tab on the area for a few minutes. If it lightens it was organic
-- Next try crushed vitamin C tabs in a thin sock or nylon. If that works it was iron
-- If the vitamin C tabs made the stain darker, it could be copper, so try dry acid in a sock

From there you'll have a better idea of what to do next. Hopefully it's just organic (algae) staining in which a slightly elevated FC level and brushing should help over time. For now though, focus on proper testing (again, consider one of those two kits above) and following those links below. They will help tremendously. Let us know how things turn out.