Black Algae in saltwater pool

[kelemvor]

Re: the extreme addition of salt.

I see three possibilities since he didn't report any obvious errors on the swcg control panel.


1. If the pool has a major leak and he's replacing a large quantity of water every month he may also need to add a lot of salt.

2. When a salt cell gets old and needs replacing it can progressively read less salt than what is in the pool. Get a Taylor K-1766 or at least some aquacheck strips to confirm salt levels.

3. If the salt cell gets a buildup on the sells. This happens if you don't ride herd on your pH levels. At 7.3 it's not likely the problem. That is, unless it was formerly out of control and above 8 or the cell was never cleaned. Get a Taylor K-1766 or at least some aquacheck strips to confirm salt levels.

In conclusion:Get a Taylor K-1766 or at least some aquacheck strips to confirm salt levels. Also, follow the manufacturers procedures to acid wash the salt cell. This will remove any buildup if that is the cause.

Any one of these would result in the SWCG not producing chlorine properly.


3 Gallons of muriatic in that pool is going to take it down to pH 6.6. Yikes.

[Watermom]

I would turn the SWCG off completely right now while you are working to clear the pool and just use bleach. Then, once things are cleared up, you can turn it back on.

Get a good kit --- Taylor K2006 or 2006C (better buy). Link is here for it and the ones that kelevmor mentioned in the post above:> http://pool9.net/tk/

(Until you registration is completed, you won't be able to see the rest of the forum while you are logged in. So, copy that link and then paste it into a browser window after you log out.)

[CarlD]

You might think that kelemvor's, Watermom's and my advice are contradictory, but they are NOT.

'mom's advice is simple: Fix the water first by manual tried-and-true methods before you attack your SWCG and potential problems.

kelemvor's advice is simple as well: See if you have a leak. THEN seek out whether your SWCG is giving you bad readings. And a confirming test kit for salt levels is something EVERY SWCG owner should have, even if you almost never need to use it.

My advice is on how to clear the pool and what NOT to do (add acid).

So...work on clearing the water and finding the leak. When that's done, address what's going on with your SWCG.

[stephen2UK]

I sent a lengthy reply, which does not appear to have posted, however I short - many thanks, I will employ all of your suggestions.

Pool was shocked with cal-hypo 73%
SWCG appears to be working fine, will switch off whilst using bleach
Water drops 3-4 inches per week in summer, but a lot less in winter - pump running each time, suggests no major leak
Will buy test kit as suggested, thanks for links
Muriatic acid is back on the shelf to gather dust
Will increase brushing as much as possible - loooooong hours at work

Thanks for all the advice

[Watermom]

Stephen, when you post it will go into a moderation queue to be approved by one of us before it will appear on the forum. We try and empty out the queue multiple times per day so it usually isn't too long before it appears. A way to avoid the moderation queue is to become a subscriber if you are interested. Subscriber posts also get priority attention when we get really busy.