New Owners, big algae problem, big money to Leslies.

[phxnewpool]

Hello all! New homeowner and first time pool owner. Bought a house in Phoenix and pool had gone completely green while previous owner vacated the home before we purchased it. Pool was great for a few weeks after we had a green pool recovery completed by a pool company as part of our repair addendum. We first started testing the pool after seeing algae within a week and saw that our alkalinity was really high (240+ range) and thus our chlorine wasn't sticking around long. A month ago our pool went solid green, used Green to Clean and shock per Leslie's recommendations. It worked, pool came back great. A week later, solid green again. We used Green to Clean again, this time no luck. We had our sand filter changed out last Monday, did the Green to Clean again on Tuesday and now we're still green. Went to Leslie's again today (enrolled in their algae free guarantee program so at least we're getting free chemicals now) and tested our water (10,500 gallon pool):

FAC: 5
TAC: 5
CH: 300
CYA: 80
TA: 180
pH: 7.5
TDS: 4000
Pho: 0

Leslie's recommended draining our pool 1' at a time in the evenings (plaster pool, obviously can't drain in the summer) and filling up with the hose and the pool water line to fill quicker and lower our TDS. When we are shocking as part of Green to Clean we're seeing a bunch of shock floating on top of the water and not dissolving. We've been dumping money into this pool and can't use it, so I'm hoping there are some recommendations from this board. Thanks, all!

 

[BoDarville]

Welcome to TFP!

Leslie's recommended draining our pool 1' at a time in the evenings (plaster pool, obviously can't drain in the summer) and filling up with the hose and the pool water line to fill quicker and lower our TDS.

I half agree with Leslie's statement about doing a partial drain & refill - not because of TDS - but rather to lower your CYA a bit. If the pool is still green, you will need to do a SLAM - Shock Level And Maintain. Lowering your CYA to about half of what it currently is will help make the SLAM easier by lowering the chlorine target. And, in order to do the SLAM, you will need one of the Recommended Test Kits along with lots of plain unscented liquid bleach.

BTW, TDS is something that can be ignored. It stands for Total Dissolved Solids, the sum of everything dissolved in the water. The problem with TDS is that it is a total of everything, and only some things cause problems. For example, if all you have dissolved in the water is salt, you can have a TDS in the 3,000 range and still have a totally manageable pool. OTOH, if you have 300 ppm of CYA in the water you can have a TDS of under 1,000 and have major problems. Pool stores love making a big deal about TDS so they can sell you all sorts of needless chemicals that will drain your wallet and likely raise TDS even more.

 

[phxnewpool]

Welcome to TFP!

I half agree with Leslie's statement about doing a partial drain & refill - not because of TDS - but rather to lower your CYA a bit. If the pool is still green, you will need to do a SLAM - Shock Level And Maintain. Lowering your CYA to about half of what it currently is will help make the SLAM easier by lowering the chlorine target. And, in order to do the SLAM, you will need one of the Recommended Test Kits along with lots of plain unscented liquid bleach.

BTW, TDS is something that can be ignored. It stands for Total Dissolved Solids, the sum of everything dissolved in the water. The problem with TDS is that it is a total of everything, and only some things cause problems. For example, if all you have dissolved in the water is salt, you can have a TDS in the 3,000 range and still have a totally manageable pool. OTOH, if you have 300 ppm of CYA in the water you can have a TDS of under 1,000 and have major problems. Pool stores love making a big deal about TDS so they can sell you all sorts of needless chemicals that will drain your wallet and likely raise TDS even more.

Knowing that this is my first pool, I have some questions before I do any draining. Is it actually safe to do a partial drain with a plaster pool when its this hot out? I was thinking we could do first thing in the morning (5 am, when its still in the low 80s) and drain/fill the pool simultaneously.

 

[Texas Splash]

Attempting a simultaneous water exchange as you noted is not as efficient as simply lowering to X-amount and refilling. Removing the water "first" guarantees that the CYA will be removed by that X-amount (i.e. 50% removal from a pool with a CYA of 100 = new CYA of ~50). Yes, it is safe to do a partial exchange of water. We typically suggest however that you don't go any lower than about 12" from the bottom or below the lowest step. Even if you decide to be extra cautious and not drain more than a 1/2-3/4 of the pool, that's better than simultaneous water exchange.

My biggest caution however is not having your own kit. Pool stores are notorious for getting CYA wrong either because of poor testing methods, lack of experience, or indoor lighting (Taylor recommended outdoor (natural bright) lighting). While your CYA is probably high, it could actually be much higher, so it would be better to know for sure where you stand by using one of the recommended test kits. I would recommend the TF-100 (link below) with XL Option and Speed Stir. It's a fantastic product that will last you all season if not more. With that kit you will be guaranteed to be in 100% control of your pool.

 

[triptyx]

Phoenix heat and dry plaster is a very bad combination right now.

If if you're going to drain, you'll need to be camped out next to the pool with a hose to keep the exposed plaster wet to avoid potential damage.

Before doing anything, however, please get an approved test kit and let's get some real numbers. Without those, it's impossible for us to help you with your pool.