Cant figure slow leak

Bonaboo1

Member
Sep 29, 2019
15
Foley, Al.
I had gone through all the test for leaks since water actually continued to pass all openings, so I went with MD plugged both drains and had quite success. After a few days I began to see 1 to 3 in. drop and wonder if the second hole down in the MD could need plugging also. I don't know what this larger hole on the side of the MD does but could this be the problem?
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,800
Pleasanton, CA
That is usually the hydro-static valve and yes, they can leak but will leak to the underneath side of the pool.

Also, have you check around the edges of the skimmers> Sometime gaps occur around the edges.

The other possibility are the light niches. If they are plastic, they can sometimes crack and/or the conduit connection can crack.
 
Last edited:

Bonaboo1

Member
Sep 29, 2019
15
Foley, Al.
O. K. Gotcha but I did check skimmer cant see leak and dye never moved I think I only thought MD and no more leak. I also ran dye around light no visable leak however I just read a thread that they can leak inside light however there is a half full water level behind glass does that cause a flag. One big question if there would be an eye draw of dye can it be fixed by replacing it?
 

Bonaboo1

Member
Sep 29, 2019
15
Foley, Al.
Well thanks for that I will definitely address ---now then is that other opening in the MD alright to close off as well without any problems; and now I'm thinking wouldn't the water leak the same as if before I plugged the first hole in the MD or does it not go out the same line?
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,800
Pleasanton, CA
As long as there is water in the pool, it is ok to plug the hydro-static line. The hydro-static line allows water underneath the pool to enter the pool so that pool does not lift up. Occasionally they will leak water in the other direction. But it wasn't clear to me from your first post if when you plugged the MD lines, that the leak stopped. If so, then the leak is in that line and not the hydro-static line.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,800
Pleasanton, CA
mas985 could you tell me if a slight drift of dye from a return can be fixed with new eye?
I'm not sure what you mean by this. If you mean it is leaking, then no, a new eye would not fix it. You need to seal the pipe where it is leaking. Why kind of pool is this?
 

Bonaboo1

Member
Sep 29, 2019
15
Foley, Al.
I'm not sure what you mean by this. If you mean it is leaking, then no, a new eye would not fix it. You need to seal the pipe where it is leaking. Why kind of pool is this?
A gunite 17,000 gal salt gen. 10 yr. Jacuzzi water feature just put a new cell on, but I really am trying to not have a technician come and spend for ultra sound because I'm in a small town very hard to find help.
I'm not sure if anyone can find a leak down deep right
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,800
Pleasanton, CA
It is possible to pressure test the entire plumbing system with the appropriate equipment. A diver could then test the pool shell penetration points. So it is possible to test everything. Finding the exact location is a different problem. If it is in the MD line, generally, you wouldn't bother fixing it and would just seal off that line. It isn't necessary anyway.

You never answered my previous question. When you sealed off the MD line, did the leak stop?
 

Bonaboo1

Member
Sep 29, 2019
15
Foley, Al.
It is possible to pressure test the entire plumbing system with the appropriate equipment. A diver could then test the pool shell penetration points. So it is possible to test everything. Finding the exact location is a different problem. If it is in the MD line, generally, you wouldn't bother fixing it and would just seal off that line. It isn't necessary anyway.

You never answered my previous question. When you sealed off the MD line, did the leak stop?
Sorry got busy---yes the major leak stopped now it's about 3 to 4 inches a day driving me nuts, I was surprised for awhile when the hot tub would all of a sudden drain for no reason never changed a thing then seemed to stop draining and back to normal, could I have a pressure prblem.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
12,800
Pleasanton, CA
So you have been talking about the spa MD all along and not the pool MD?

When the spa level dropped, was the water level equal to the pool level? That could be a check valve issue. Water is draining from the spa to the pool.
 

Bonaboo1

Member
Sep 29, 2019
15
Foley, Al.
Sorry misunderstood I'm sorry the pool is the loss and plugging pools MD has considerably slowed the loss of water however there were 3 days the hot tub draining back to pool now has stopped, I have no idea what caused this because now it's fine.
The hot tub is up out on deck and has water fall feature and cant compare levels.
I'm going to see if there is anyone to do the pressure test you have suggested and maybe the light has a leak--- I don't know just that about 4 inches a day seems major, but before I plugged the MD it was more like 20 inches or even more a day. I let it drain go to see if it went past all openings to rule them out and twice it went to bottom. The scariest is it doesn't seem to be many people in the business here that offers this type of help.
Cant thank you enough you have helped me.