What is delaminated pool plaster?

[@drewpeterson6002]

I'm a perpetual DIY'er and just bought a house with a 50 year old concrete pool (last summer we bought it). I recently discovered a number of "hollow" spots in my plaster. I am losing 2" a day of water and while I recently filled my pool for the summer, I think I'm going shut my pool down and let the water drain down to see where the leak is. It's already past my skimmers and it's still going down. I dye tested the main drain and that's not the issue. Last year, a 3" chlorine tablet somehow sat on the bottom of the pool and left a nasty yellow stain. Not knowing anything about plaster at the time, I took sandpaper to the yellow stain. I got most of it off, but I'm thinking I may have done serious damage to the plaster layer. The last time the plaster was done was in 2007 and there are definite cracks around the pool in the plaster layer. I found many delaminated spots by the deep end skimmer and used a chisel to break off those hollow spots down to the gunite. The concrete underneath these spots was cracked and peeled off, too. There was a blue, almost plastic/fiberglass layer under the white plaster...what is that? I'm going to use Pool Patch to re-seal the areas I chipped off. Could the water loss be contributed to the old plaster around the pool and water just leaching through it?

[@timothydbaker9950]

Sounds to me the blue undercoat could have very well been the company that replastered's attempt at a bonding agent speaking in the world of pools have to be careful only certain bonding agents actually work failing to apply bonding agents or applying faulty ones cause delamination in plaster in the first place and that could absoulutely be a reason why you are having a leak you mind as well get that problem taken care of now since you are doing other work on the pool better to fix everything before you fill it hope this helps

[@romero1011985]

Hello...Very informative video.thx...Quick question ...I had just recently got my pool replasterd this week and noticed a crack in one area. Is that something normal.?

[@timothydbaker9950]

Could be delamination or could be a surface crack