Printable View
I have had a heck of a year clearing the cloudiness of my pool and have posted about that issue in the algae forum. So I am fighting that.
My sand filter is less than a year old and I find some sand in the backwash and was wondering if it was normal for any sand to come out in the backwash. There may or may not be sand in the pool as I don't know if I have dirt or sand because of the cloudiness.
Thanks!
My shoot-from-the-hip guess is that even though it appears to be a 350# sand filter, the pump is too powerful for it.
Either that or you have a damaged lateral in the filter that was defective or damaged during assembly of the filter.
That's my guess.
Carl
I am also of the opinion the pump is too powerful. It was here when I bought the house and I changed the filter but not the motor. The line is a 220 but I think my motor could go down a half a horse power when I replace it.
Should I look inside the actual filter as it is not yet a year old? If so, what do I look for?
Thanks!
Well, I think you can use PoolDoc's trick of throwing about a cup of DE in the skimmer--make a slurry in a bucket first and dump that in. If the DE blows out the return into the water, you've probably got some damage.
Ben, if I didn't get the technique right, please correct it...thanks.
There are alternatives: Replace the impeller with a smaller one. Smaller motor.. etc.
Carl
Not saying that your pump is not too powerful ............ but just saying that it is normal to lose a little sand during backwashing.
First, I thank you for your help.
When I vacuumed to waste, there was quite a bit of sand on the ground from the waste water so I have quite a bit in the pool. Before I get a less powerful pump, I want to check inside the filter to see it something is broken and how much sand is left.
When I remove the top, what is it I should see and check?
The DE test is the easiest, fastest and cheapest test of your sand filter. Do yourself a favor and start there. 10# of DE should cost no more than $10, and you can use the rest to improve your sand's filtering capability as part of your normal routine. Most of us who have sand filters use the DE trick routinely--I'm still on the first 10# box after 4(?) years, at 1/3 cup each backwash.
As for checking the filter: Here my expertise is a little less than some other folks. But most top-mount sand filters have very simple internal plumbing that looks a little like an upside down umbrella with just the ribs, no cloth. The horizontal "ribs" are called laterals and usually fold up (like an umbrella) to the central vertical pipe for removal or installation. One of these laterals may well be cracked or have the holes in them blown out.
Here's the Catch-22:
You can't see them--they are buried under sand. So you'll have to dig out the sand and empty the tank of sand to be able to examine the laterals for damage. If you can save the sand, you can, as long as it is not gummed up. Or you can replace it, only using pool filter sand (sorry--pool store) and only using the amount your filter is rated for, which I believe is 350# (7 bags).
Also, whether the laterals are OK, or you have to replace damaged ones, they usually have a molded support in the bottom of the tank. Be sure they are seated correctly before you add more sand. I THINK you can get away with adding the sand dry, but your manual may tell you to mix it with water so it settles nicely. Again, I'll defer to other folks here.
But try Ben's DE test first, of a cup or 2 of DE in a slurry (a bucket of water with the DE in it floating around) into the skimmer and see if you get lots of blow-back into the pool. If it's all OK, flow should drop and pressure on the gauge should rise, then you'll need to back wash it out.
(Corrections and adjustments from "The Gang" are welcome!)
Carl
Thanks Carl
I will give this a shot as it seems simple. Thanks for your time giving this detailed answer.