New build in South Texas

[martinkennedy]

There are 3 drains in the catch basin and 6 returns at the shallow end of the pool. It has a Pentair variable speed pump that only controls the flow of water over the infinity edge. It's the 3" line on the left of the picture

[martinkennedy]

Ultimately when all the wiring and controls are done the pump for the infinity edge will start when any of the water features that put water into the pool or basin are turned on. The water bowls, the exterior mini waterfalls on the side of the raised beam or the herons

[PoolDoc]

One thing you'll need to watch for: any time the edge is ON, you'll be stripping carbonate alkalinity and raising the pH. The process won't stop till the pH is around 8.0. It will take time to learn how to manage it, to maintain carbonate saturation. But, given all the tile grout and plaster you have, it will be critical.

How were you planning to treat the pool? There's something feeder-looking between the filter and the Pentair pump. What is that?

What's the Pentair driving? An infloor cleaning system?

[martinkennedy]

The other Pentair pump is running a few of the water features as well as an in-floor cleaning system. The 3rd pump will be running the bowels. We will be using Tri-Cor tablets for chlorination. With the aeration that we are doing it should help with the CYA. I understand as you have pointed out, that with the water flow into the catch basin that it will have an impact on the PH. I am having an outside service take care of the pool but I also have a test kit of my own to keep another set of eyes on the readings. Thanks for your continued comments and advice.

[PoolDoc]

Ok, thanks for the info. One more question: in looking through the photos of the pool, I noticed a number of outlets on the wall of the pool closest to the house. What are those?


And . . .

The 3rd pump will be running the bowels.

Huh?

With the aeration that we are doing it should help with the CYA.

Not sure what you mean; aeration has no effect on CYA levels.

[martinkennedy]

Sorry bowls not bowels. With the water falls and mist and evaporation that goes along with it, the need for replacement water increases. Replacing the water at a higher rate in effect acts as a counter balance to higher CYA. This just means I will go a longer period of time before I will have to drain and refill the pool to lower the CYA created by using chlorine pucks in the chlorinator.

The outlets at the end of the pool are the returns for the catch basin and the other are the returns from the skimmers

[PoolDoc]

Thanks for the info. I think I can visualize the system functionally, now.

With the water falls and mist and evaporation that goes along with it, the need for replacement water increases. Replacing the water at a higher rate in effect acts as a counter balance to higher CYA.

Actually, that's not correct. Losing water to evaporation has no effect on the total quantity (mass) of CYA present in the pool water, just as solar evaporation does not lower the ocean's salinity. The reason is that the water vapor -- evaporated water -- is essentially distilled water, free of all chemicals. Some volatiles may be present, but CYA does not have a significant volatile fraction.

There are 3 known ways to lower CYA:
1. Drain (as liquid water, not evaporate as water vapor) and replace.
2. Precipitate with melamine, making a huge mess.
3. Biodegrade with heterogeneous 'slime' composed of algae and soil bacteria. This happens naturally, but is unpredictable as to rate of degradation (2 weeks to months) and endpoint (nitrogen gas, nitrates, or ammonia).

[martinkennedy]

To be clear, I am not talking about evaporation by itself. I am talking about the mist created from the waterfall's (I have three) over the infinity wall and the other two mini falls as well as the mist and water disbursement because as the water falls the wind carries some of it away. If you have ever been to Niagara Falls that mist that is in the air is a direct result from the falls. This necessitates the need for more water. In effect I am replacing more water than a standard pool. It will not completely remove the appropriate CYA, but will delay the need for water replacement on a wholesale basis

[martinkennedy]

More work going on. We still have about 6 more weeks of work

[martinkennedy]