Vanishing Edge Pool question

[SFBayArea]

Hey guys,

I have a question to those who have vanishing edge pools and to those who build pools with vanishing edge.
I have a PB company which consist of two guys - partners. When they were building my pool they had a split of opinions (which I was only told now), where to install auto-filler. One guy was saying that auto-filler should be installed on the lower level where the small vanishing edge pool is and another guy was saying that auto-filler should be installed on the main pool level. Well, they ended up installing it on the main pool level. However, one thing I noticed now is that by running over the vanishing edge some of the water (very little of it) spills out on the deck and with time water level in the small pool getting lower and it does not autofill.
Does that mean that they had to install the auto-filler on the lower - vanishing edge pool?

[TSH Tech]

The auto-filler would have been best installed in the trough(lower pool).

When the auto-filler is installed in the trough, soon as the pump turns on, the pump takes water from the trough and pumps it up to the upper swimming pool ensuring it is filled. As the water is being depleted from the trough, the auto-filler maintains enough water level inside the trough to keep the pool supplied with water. As the pool turns over water from the trough up to the pool and over the spillway, eventually the water level equalizes and the auto-filler shuts off. Also keep in mind, any time water spills over something, there is going to be a certain amount of evaporation.

Now, I wasn't there, I don't know what those two were thinking but I can take a guess. I would assume they installed the auto-filler in the upper main pool to ensure the overall look of a full pool was maintained. But the reality of the situation is, the filler is best served in the trough area. Here's the main concern: If the trough goes dry, then the infinity edge spill-way effect will not happen. The trough is the starting point for water circulation in an infinity edge pool.

It won't hurt anything to have two auto-fillers, but the trough definitely needs a water fill source.

[SFBayArea]

Thank you for the post. I assume, "trough" is the proper word for the small vanishing edge pool, right?

Yesterday night, they finally connected auto-fill to the water line. This morning I came out to see the level of water in the trough and ooo sheet, it is overfilled and water running down the hill and keep running. I think it was doing so all night long. Shoot! What are my options now? They already poured concrete around the pool .

[TSH Tech]

First, if the water is continually running out of the pool and down the mountain, shut it off.

Brand new pool? Warranty?
The builders need to get back out to your pool and troubleshoot what is going on. This ball is in their court. They own this problem until it is fixed.

wow, sorry to hear a rough start to what sounds like a nice pool

[SFBayArea]

Thank you.
The PB said he'll come back on Tuesday and install another auto-filler at the little pool level.

[Guest]

You must put the a/fill on the lower level. If the size of that sump has been properly calibrated, and it it properly filled, you will get the proper vanishing edge effect when the v/e pump is operating. Think about it. You must raise the water level of the whole upper pool about 1/4" to have a good v/e effect. All this water must come from the sump. The autofill thus must maintain a minimum volume in the sump. Now you cut off the v/e pump, and the upper pool is full to the v/e edge. If you started with an upper pool that was down a half inch, the sump will be several inches low, plus evap losses while running. The autofill must make this loss up in the sump.

Also note that if the upper pool is too low, no sensibly sized sump will be sufficient, so there is some argument for an autofill on the upper pool as well, calibrated to maintain a level sufficient to keep the sump from pumping dry before the upper pool begins to spill.

Vansishing edge pools require considerable calculation, and you should insist on v/e pool references, and CHECK THEM out. Remember, the proportion of fools and thieves is higher among PB's than in most any other profession...

[SFBayArea]

Thank you guys.

My PB added autofiller at the lower level where the v/e pool is and plugged autofiller on the main pool level.
However, I think the water level in the small pool is too high. Even when water is two tiles below edge if I swim without vanishing edge pump on, I overfill the little pool in 15 min or less. I told this to my PB, he said he will come and put a third line of tile and drop water level by another 3.5" in the little pool. Hope that will fix the problem, otherwise every time I go swimming I will have to turn on V/E pump.

[Robert K]

When my pool was installed the builder set the pump to run for 8 hours from 10 AM to 6 PM. Since the pool always looks full he said to check the trough periodically to see if water needed to be added due to evaporation. We live in Florida, so this is an all year process. I got into a routine of checking the trough weekly and adding about 6 inches of water. One week the trough was down 12 inches. I didn’t think much about it, added the 12 inches of water, and the next week the trough had lost the usual 6 inches. The 12 inch loss occurred off an on over the next few years until one week I noticed that the trough was empty. Looking for the cause I found a twig caught in the backflow flapper valve. During the 16 hours that the pump was off water had flowed from the pool, through the valve, and up into the trough via the two drains at the bottom of the trough until the trough overflowed causing a loss of water from the pool. After removing the twig the old routine of a 6 inch loss continued until one day it happened again. This time I had been away for a few days. When I looked at the pool the level was down 2 feet, which is the height of the trough below the pool. Thousands of gallons had been lost.

The solution:

I rescheduled the pump to run for 6 hours from 11 AM to 5 PM, then to run every 3 hours in between for a half hour (i.e. 8 PM, 11 Pm, 2 AM, 5 AM and 8 AM). The total run time is about the same but now the pump puts water back into the pool before the trough can overflow if something gets caught in the backflow valve.