Green pool...

[Ahorejsi]

This is our first year owning a pool. We got an intex 18x52 with the sand filter and swg, thinking that it would be 'maintenance free'. It has been great for the last two months, but going downhill quickly in the last two weeks. I think it started because our salt levels got way off. Mother low salt indicator kept coming on so my husband would just keep adding more salt. We could tell by the feel of the water that there was pleanty of salt, so I used google and found someone who shared that sometimes the salt detector gets crusted over with salt and needs to be cleaned by soaking in vinegar. We did that, and of course as expected, then the 'high salt' warning came on. My hubby tried letting out some of the water and refilling it, but he thinks it's still too high in salt. Algae started to grow, so we brushed/vacuumed and it looked ok. We went away for a three day weekend and came back to a green pool. My husband is convinced that it's low on chlorine, and that if he drains more water out, and gets the salt level back on track and boosts it, that it'll start clearing up. "Because the user guide says that you shouldn't need to add anything else, that the swg keeps everything in check." I'm not so optimistic. I think we need to get a test kit and start using the tfp method. All we have is the little test strip that came with the pool. The chlorine level is .5 and the fc and ph are at the "worst/highest" levels available on the test strip. (8.4 for ph and 240 for ta)

So tell me, is there any chance that draining some of the water, refilling, and getting the salt levels back in place so that it's generating the right amount of chlorine will turn our pool from green back to blue/clear?

 

[JasonLion]

Welcome to TFP!

There are a couple of things you need to do, and the first one is get a complete set of reliable test results. The best way to do that is to buy one of the test kits we recommend (TF100 or K-2006), but a set of results from a pool store will do in a pinch.

Meanwhile, replacing a little water sounds like a good idea. I would go cautiously, you may not need to replace all that much, and see when the SWG starts being happy with the salt level.

 

[Isaac-1]

To follow up on that, an SWG is good at maintaining chlorine, but not so good when you need to clear a green pool, often they simply can't generate enough chlorine to get things clear and need a bit of a boost. Even if they can manage it, it is still better to manually add chlorine while clearing a green pool to avoid the excess wear and tear on the SWC cell. For this liquid chlorine / plain bleach works best, but without a set of accurate test results you are flying blind on how much and how often you will need to add the bleach. (all dry chlorine products also add other chemicals that you may not want or need in your pool, cal-hypo adds calcium, and both dichlor an trichlor also add CYA, bleach just adds a trivially small amount of salt).

Ike

 

[pwrstrk]

What Isaac said ! Good advice.
Welcome to TFP !! ?