Small Pebble Under Liner

by Amy
(Southern Wisconsin)

We are getting ready to winterize and close our pool. I was inspecting the liner this morning and found what looks like a couple small pebbles under the liner on the bottom of the pool.

Is this something I need to worry about? We just put the pool up this spring. It is an 18' pool.

I was wondering if I should try and patch the area before we winterize the pool?

Thank you for your help, I love reading your pages!

Hi Amy.

I wouldn't patch over the pebbles unless you really thought they were poking through the liner. It is often possible to take the rubber end of a vacuum pole and poke the pebbles down, by lightly tapping on them. This can usually be done without any damage to the liner. This works well if the liner is on a sand base.

If the ground under the liner is on the hard side pounding the pebble down could possibly puncture the liner. At this point I would put a patch over it. This seldom happens, however, but is possible.

Bumps Under Vinyl Liner

by Amy
(Westminster, MD)

My above ground pool is only about a year old. I recently noticed hard little bumps under the liner around the entire pool just about a foot below the water line.

Can you tell me what these are and what I could possibly do to prevent any problems they could cause with my liner?

Thanks.

Hi Amy.

That's not a question I can answer with a definite "this is your problem", but I will give you some possibilities. Sand behind a liner causes bumps but this is way to high up the wall for sand and it would have been there since the beginning.

It is probably something that is developing, or growing, on the wall. I have seen calcium deposits do this. They are usually caused by water getting in behind the liner from either leaky fittings or a hole in the liner. The wall itself could be corroding in some way. I have seen aluminum walls rust in this way, first causing little bumps and then holes in the wall. On a steel wall it could be the paint bubbling, reacting to something possibly. It is even possible that rust is developing on the wall.

If it were my pool I think I would want to know what it is. You just need to drop the water down about half way and remove a couple of top rails. You can then remove a stabilizing rod or two and get in behind the liner. That should give you some indication about what is going on.

Stopping Pebbles From Rising Up

by Bob C.
(Howell, NJ, USA)

I am installing a new above-ground pool that is three feet larger than the one we had that collapsed. I had to excavate into a slope in the ground but there are small pebbles left from that.

I have been told I have to get absolutely every one up before I put in new sand and a new pool. Is there something I can lay down to prevent any missed pebbles from rising up through the sand and making a bump in the bottom of my liner?

Hi Bob.

Pebbles rising up are really not that big of a problem if the ground prep is done correctly. If the ground is leveled and packed, and then raked smooth, you should be fine. During the leveling, packing and smoothing processes you will be removing all of the rock and pebbles that you can.

If you add a couple of inches of sand on top of that most of the time you will be just fine. The weight of the water on the ground actually prevents pebbles and rocks from rising. If you remove them prior to adding sand they should never become a problem.

Added protection can be in the form of landscaper plastic or a pool pad. These can be added as a barrier between the sand and the dirt. Most of the time when someone says a pebble rose up into the liner, it was something that just got mixed up in the sand during the moving and spreading process. The sand will compress with the weight of the water. A rock may not be noticeable when you are smoothing the sand, but when the sand compresses, there it is. That happens even to us pros.

If something ever does appear as a bump in the bottom of the pool, a couple of light taps with a rubber mallet makes it disappear. I have had the pleasure of taking a few afternoon dips in order to tap down a pebble or rock.

Pebbles or Sharp Object Under Pool

by Teresa Haynes
(Sumter SC)

We just had a new liner installed and I was not there to oversee the install and my first clue that these people were not experienced installers was I had some small holes where dirt had shifted and they had to borrow bagged sand {playsand} from me, they didn't have any on the truck. Then I asked the pool company owner if I needed a soft bottom or vermiculite added and he said no you don't really need it so I opted not to get it.

Now a week later I was walking around my pool and there are about five or six stones under my pool, one is really sticking up and I'm sure it will tear soon. He said the only thing I can do is patch it when it leaks!

He also denied telling me I didn't need the soft bottom put in. I really believe he didn't have it on the truck and didn't feel like going back to the store to get some. I'm wondering if there is anything I can do besides "waiting it to leak to repair" Also they didn't even put any sand or anything on the bottom. I paid extra for some spray for weeds and I'm not sure if they even did that. I feel I have just thrown 1,200 dollars down the pool drain!

Hi Teresa.

Every once in a while large pieces of sand do pop up during a reinstall. It has happened to me so it is hard to say if your installers were bad or not. A perfectly good sand base, one the that I would recommend nothing but a brooming to smooth, can have a pebble or two poke up.

I would tell my customers to do this. Take the rubber end of the vacuum pole and tap on the sharp point. When a pebble pokes up in a sand base it is usually very easy to tap it back down.

If my customer tried some very light tapping with no results I would come out and see what I could do.

I would dive down to the bottom with a rubber mallet. I would again give it a few light taps. Most of the time this would take care of it, well, just about always.

There were a couple of times the liner may have been torn. I would then apply a small patch over the hole. The patch would be from the same liner so that it was invisible. Anytime I patched a pool I gave, in writing, a guarantee that the patch would last as long as the liner. They always have. A properly patched pool does not take anything away from the length of time you well enjoy the liner.

Pool Bottom is Lumpy

by Lynn
(Grand Rapids MI)

My husband and I have a 2 year old 24' round above ground pool. Last year we drained it down dry to clean up a green pool problem.

We ended up walking in it and disturbing the sand and leaving "footprints" in the bottom, which is now very hard to vacuum. What is the easiest way to fix this problem?

Lynn

Hi Lynn.

The only way to fix this problem is to completely drain the pool. You can then pull the liner back and smooth the bottom. I don't however, recommend this. You were probably very lucky to be able to drain, clean, and re-fill your pool without the liner shrinking up and becoming unusable. The next time you drain it you will probably be changing the liner.

Liners that are just a year or two old can usually be drained and re-filled without to many problems. After that, it is really never safe to completely drain the pool.

I would just live with the lumpy bottom until the time comes to change the liner, then I would smooth it out real nice and stretch the liner into place is a way that does not disturb the sand base.

Above Ground Pool Liner Installation