Sand in pool never ends!

[Swimmr]

Hi there - this is my first post (newbie alert).

We have a 20'x40' inground pool, chlorine.

In 2010 we had our pump rebuilt (was still working but was VERY loud), and it has been working fine (from what we can tell) since. In 2011 or 12 our sand filter "died" (honesty don't remember details on this), and it was replaced with a new one. Fast forward to spring '13. We replaced liner of pool due to a number of small leaks and just general wear and tear of liner. Everything seemed OK for about a month - then we started getting sand in the pool. We called pool company, and they said we likely needed new tubes (lateral etc inside of filter). That was last September '13. They replaced laterals etc (technician mentioned it was funny because existing tubes looked OK) and replaced the sand. Everything seemed OK. Weather cooled significantly after that and we closed pool for winter. We opened pool this spring ('14) and within a week of opening the pool - more sand. Very cloudy water, sand under jets, etc. We called pool company back - They are stumped. When they opened the filter to look in it, they found it had less than 1/2 the sand it should have had in it. They had some experience with the brand filter we had going bad, so this past Monday they replaced the filter with a brand new one. Since then we have vacuumed 2X, but seems like cloudiness is getting worse instead of better. Pool company is going back today to take a look, but I get the impression that they are stumped. Have verified with them problem is not pool chemistry.

What could be causing this? I can't believe we got 2 bad filters in a row. Could this just be sand left in lines from before? It just seems strange because it would be gradually getting better rather than worse, wouldn't it?

Other potentially useful info: pump and heater are original - at least 15 years old (we didn't install pool, so can only ballpark it) No more than 18 years old for sure. Pump has been rebuilt, but seems to work fine. Heater has stopped working a few times, but has been repaired. We also find that we don't get very good pressure of water from the jets coming back into the pool. One jet is strong, the other about the same, and the third is typically weaker. I also don't think we get the best pressure through the skimmer (evident when vacuuming). It does work, though, just we find we have to backwash sometimes in the middle of a vacuum in order to keep the pressure up.

Does anyone have any suggestions? I would love to have my pool be swimmable this year...

 

[Casey]

Welcome to TFP. I can't really help you with your sand filter because I don't own one. Never have, Never will because I love my DE filter. Personally, if this were my pool and I was still having issues, I would trade it out for a Cart or a DE filter and be done with it, clear the pool and enjoy many seasons to come. That may not be as simple as it sounds but that's the best advice I can give you from my stand point.

Someone with more knowledge will be along shortly to offer their advice to you.

Welcome to TFP! Hope you stick around and enjoy the site!

 

[jamis]

Make of filter and model?

 

[TreeFiter]

So after replacing the filter, are you still getting significant amounts of sand in the pool, or just cloudiness?

When they replaced the filter, did they replace the Multiport too?

You said you have ruled out chemistry as the problem. How did you do this? Can you provide a set or reliable test results?

If a sand filter isn't blowing sand into the pool, and it isn't restricting flow severely, it is working the way it should. Those are the two ways in which they typically fail. I highly doubt that a new sand filter is already clogged up and in need of changing the sand. Have you backwashed recently? That could be the cause of reduced suction and return pressure.

If I were to guess at what is going on, the pool sat without running while you waited to replace the filter. By the time you got it back up and running, algae had already taken hold, and the pool turned cloudy. The pool store says the chemistry is fine, but its not. It might be fine for a clear pool without algae, but once algae starts to grow, the rules begin to change. If you post an accurate set of test results, we should be able to show you why your pool isn't clearing up.

 

[schurtj]

Make sure after you backwash that you set the selector to "RINSE" and run pump for 20 to 30 seconds before changing back to the FILTER setting. This helps to clean out the lines and settle the sand so it doesn't end up spewing into the pool from the returns. I made this mistake before and it definitely puts sand in the pool.