Do you ever have to replace sand in a sand filter

[psteward]

I've read a couple of threads about backflushing etcetra and I've seen different opinions on replacing the sand. I have been using my equipment for three years and I have no idea if the person that owned the pool before ever changed the sand.
I took the top off this year and put hose in it to really clean it. I took sone grey gunk off the top and it seems to work fine (but it did before too).

[CarlD]

IF you aren't sure how the sand was maintained, replace it. Be very, very careful of the laterals so you don't damage them.

Sand is cheap--$5-$6 per 50 pound bags.

But once you change it, if you maintain it properly and aren't using too big a pump, you should be able to go years and years without changing it again--I'm on my 4th year, Poconos is on his 9th with the same sand. Some others respectfully disagree with us, but if you aren't having problems with water quality or clarity, I don't see why. But if it's gummed up with Bacquacil goo, or some other additive, or is HORRIBLY infested with algae (can and does happen--did to a friend) then, again, sand is cheap--change it.

Of course, if you ARE having problems, then changing sand may be appropriate. I also believe if you have to fix or replace the laterals, new sand is in order. Poconos disagrees with me--I think it's a matter of preference.

[Poconos]

No Carl, I don't disagree. I'm cheap. I had to dump my sand to add something to the filter to let me drain it better for Winterizing and I just put the old sand back. Sand looked perfectly OK to me so I just reused it.
Al

[CarlD]

LOL!

This being "cheap" has led Al to some VERY interesting inventions and activities....He's the best of us mods on equipment too!

[egk61]

I have awful dirty dark green water even after days of shocking. I too am beginning to think I need to change sand. I usually can just shock and get past this, but it doesn't seem to be working. In addition, for the past few years there has been a small amount of sand in my polaris bag every time I use it, I would assume this adds up over time. I also don't seem to need much of a backflush when I do so, seems like I used to get gunk out for several minutes and now hardly anything. Could all this point to need for sand? Is this a special item or just regular old sand? The stuff in my polaris seems fine and white. Also, should I remove old sand or just add on to what is there? THANKS IN ADVANCE!!

[Branzer]

Hi...I just finished clearing a terrible black/green-then-white cloudy mess (late opening) with the help of everyone here (read my story, if you'd like under "Calcium Precipitate Cloudiness...").
We changed the sand in our filter, which was 5 years old, about half way through the process and I really feel it did a lot toward clearing the problem(s).
But, you really do need to get a good test kit, know your CYA so that you can shock to the appropriate level and stick with it. New sand won't do it all, though it is worth the effort. My husband and I were horrified by the small opening in the top of our filter, but after about 30 minutes of careful scooping, we were able to turn it on its side and speed things up (350 lb. filter).
Good Luck!

[tenax]

once per season, i check my sand for it's flowability..in other words..can i put my arm in and move sand around easily throughout the filter? what i don't want to do is wait for 3 or 4 years, check it then and find out it's hardened up. i don't think you can do much at that point except buy a new filter (at least, that's what the pool store says and i'm inclined to believe them as i've seen filter sand that is in hard chunks, bottom half is hard, etc. my sand is at least 5 seasons old and likely longer so i ordered 2 bags of zeobrite and am going to change my sand out to that this fall..then in terms of how long there has been a material in the filter, i know exactly what i'm dealing with. (my problem is that the prior home owners were terrible at maintenance in general around the home..even little things like tightening a door handle, so it maybe 5 seasons old..or it could be 15) my sand is still very porous at a check a few weeks ago so i would like to believe it's no more than 5 years old..also, i have no idea how long it takes sand to go from porous to hard in a filter, which would be nice to know.

[waterbear]

I have said before and I will say it again that yearly cleaning of the sand with a garden hose stuck into it and possibly using a commercial sand filter cleaner will keep the sand from caking and forming a hardned mass in the filter and keep the filter running at top efficiency.

[Poconos]

All I can say is I'm on the ninth season now with the same sand. Every time I winterize I remove the valve assembly and drain, and have yet to see any clumping, caking, or anything else wrong with the sand. The one time I had to suck the sand out for an 'engineering modification' I likewise saw nothing unusual all the way to the bottom.
Al

[egk61]

Thanks to all, I did end up changing it, the good advice of the pool center was "when in doubt change the sand" He noted that sand is cheap and you can spend lots of $$ on chemicals trying to fix the issue (and still end up back at the sand). Didn't even try to sell me chemicals!! He told me to stop when I could see the laterals so they would have support and not break off, and to fill the tank about 1/2 way with water to lessen the shock of the snd on the laterals when dumping it in. Time consuming, but easy. I seem to be able to clean up now so I guess that really was it!