My sand filter sucks, new filter options?

I have a brand new sand filter and it just WILL NOT filter for anything. I have a pretty dirty pool with dead algae. I get 2-3 widths of vacuuming and the returns start pouring out green water during the vacuuming process. Backwash---rinse----filter and get 2-3 more widths. Repeat this cycle 6-8 times and get 3/4 of the pool done. Then......I have a cloudy pool and need to put more water in.

Previously, I've added DE to the sand filter. I have added like 3 full cups to get 1PSI increase. Then after a day or two.....the pressure will shoot up from 13PSI to 20PSI. Apparently, my sand filter doesn't like DE for some reason.

Run the Aquabot Viva (2 micron filtration NOT) and it just pours a steady stream of green out it's exhaust outlet.

So unless someone has any advice....I'm in the market for a brand new DE filter and pump. My pump is fine, but I'm thinking it would be in my best interest to replace it all at once. The current pump is a very old Hayward (I think) and is so worn I have no idea of model or HP rating, but it's one speed.

My pool is an 18 x 38 rectangular inground vinyl. The deep end is maybe 8 to 10 ft deep (not sure).

Can anyone recommend an APPOPRIATELY sized filter and new pump?

http://www.poolforum.com/pf2/showthread.php?t=5423

This link shows what kind of gook I'm filtering up. I'm not sure if it's from the filter or is just dead algae, but my heart tells me it's from the filter.

Last year on my DE filter, it was an algae free summer other than a few SMALL outbreaks. This year, the only thing that changed is the new sand filter and my pool just plain sucks. :mad: Still using bleach and borax and all the numbers are fine just like last year.

my very inexperienced take on your filter 'not liking' DE... perhaps the pressure is shooting up because the DE is working and trapping so many particles... as your media gets full of stuff, the pressure goes up, right? so I would think if you were catching all the very fine stuff it could cause a large rise in psi

It sounds also like you have put a LOT of DE in your filter... others here use less than a cup of DE to get the 1psi rise... did you add it VERY slowly? or perhaps you have a huge sand filter?

When you vacuum your pool, you need to vacuum to waste. Do not vacuum to the sand filter. It will infest it with dead algae. After vacuuming to waste, backwash your filter just to make sure you get rid of any algae in your filter. Then go to rinse and run in the rinse cycle for at least 30 seconds. When water is clear, go back to filter. Green water should not be coming out of the return. Also, make sure you turn the pump off each time you change the handle between filter, waste, backwash, etc.

It will take a while, but your pool will clear up. Don't forget to brush your pool aggressively after vacuuming. You also need to maintain a high chlorine level based on your CYA numbers to insure you've killed off the algae.

With a sand filter, always vacuum to waste when dealing with lots of dead algae.

Hope this helps.

bomber,
If you're getting algae, I think we can conclude that your numbers are not fine. Insufficient chlorine for your level of CYA is by far the most likely reason for the problem. While poor filtration might exacerbate an algae problem, I think it unlikely that that's the root cause. Can you post a full set of numbers?

On your sand filter, what size is it? Does it have sufficient sand in it? Too much? Does it have filter sand and not play sand in it? A properly sized and properly functioning sand filter won't have the problems you're having.

Cheers,
Kurt

Algae isn't a filtration issue. It's a sanitizer issue.

I can post full numbers when I get home later, but from memory:

Stabilizer: 60
Chlorine: 5

The only thing that's kinda high is pH which is at 8.2

If I were to vacuum to waste, it would probably take a week to do so as the water level would go down and down and down with vacuuming. I shouldn't have to do this as I could vacuum my pool on my old DE filter with 6 inches of muck and never have any filtration problems, the water always came out clear as a bell from the returns. I only cleaned my DE filters once a year and then only for fun to remember the process.

Last year w/ DE filter = wonderful pool
This year w/ sand fitler = I want to fill it in

The issue is NOT with chemicals, that I'm sure as I have a wonderful test set and am a chemical nazi. I'm not sure if the green stuff is algae or is some weird crud the sand filter is spewing out. I assume it's NOT algae since my leves are and always have been fine since finding this site.

Don't know the sand filter numbers as I have those at home. The pool people set it up and we haven't touched it since the install.

*backstory* Went on deployment to the Persian Gulf in Sept. Removed/cleaned DE filters for the wife before deploying. They are 100% PERFECT. Pool people come to close the pool and ALL 8 FILTERS are suddenly bad and need replaced. :rolleyes: They tell her it will be the same price for a new filter, so she says go for it without any training/advice/options given to her. They just push the new filter and I get stuck with it. I'll be calling the pool place today as I've had enough with trying to figure this out. Unless they have an epiphany for me, I'll be buying a DE unit + pump from somewhere else.

DE filter size/brand + pump size/brand would be nice if anyone has any suggestions on what I need.

[quote=Unabomber007]I can post full numbers when I get home later, but from memory:

Stabilizer: 60
Chlorine: 5
With a CYA of 60 you need to be keepingh the chlorine between 5 and 10 ppm. If it hasn't been kept consistently at or above 5 ppm that is very likely why you have the algae.

The only thing that's kinda high is pH which is at 8.2
A high pH will exacerbate the low chlorine level.

If I were to vacuum to waste, it would probably take a week to do so as the water level would go down and down and down with vacuuming. I shouldn't have to do this as I could vacuum my pool on my old DE filter with 6 inches of muck and never have any filtration problems, the water always came out clear as a bell from the returns. I only cleaned my DE filters once a year and then only for fun to remember the process.

Last year w/ DE filter = wonderful pool
This year w/ sand fitler = I want to fill it in

The issue is NOT with chemicals, that I'm sure as I have a wonderful test set and am a chemical nazi. I'm not sure if the green stuff is algae or is some weird crud the sand filter is spewing out. I assume it's NOT algae since my leves are and always have been fine since finding this site.
I think you're prematurely ruling out the most likely cause of the problem; insufficient chlorination. There are many people here using sand filters who don't have any of the problems you're describing.

...
quote]

If you don't indeed have algae, the problem may be with your filter but the eastiest and cheapest first step woould be to bring your chlorine to shock level (>= 20 ppm for your CYA level) for a few days or until the water clears and you can hold the FC level overnight. If that doesn't work, I'd open up the filter and inspect for the proper amount and type of sand (filter sand is vey fine).

By the way, have you talked with the guys who installed the filter about the problem?

Best of luck.

I haven't talked to the filter guys yet, but I plan on it tonight. I will try to bring the pH down and shock the heck out of the pool today.

It's just darn frustrating as I NEVER had any issues with my old DE filter. With it, it would filter everything and ask for more. Backwashing every 5 minutes is not my idea of good filtration.

I have no idea about the new unit as when it was installed my wife got ZERO training and not even a manual, which I had to download. The manual really, really sucks as it doesn't go over anything. I don't even know how to open the unit and look/check the sand or any of that. :(

Did you check to see if anything in the filter is broken? Here is a thread that you may want to read:

http://www.poolforum.com/pf2/showthr...en+sand+filter

Unabomber,

I'll bet if you post where you live, someone will happily purchase that filter from you. You'll cut your losses and get what you want......it should sell easily for a fair price.

Went to the pool store yesterday.

Bought some pH down (yes, I overpaid, but I digress) and some floc. Added the floc, but apparently I got the weak, watery stuff as the WalMart brand works MUCH better. Looks like I'll have to go to WalMart today and get the good stuff. Anyways....

The pool store guy kind of agreed with you folks that it's probably a sanitation issue more than a pump issue. So I shocked the ever living hell out of the pool. I'm sure it's over 20ppm now. I'll check it later today and add some REAL floc, recirc, and vacuum all to waste either late tonight or tomorrow.

I REALLY hope this is the cure and I just need to keep my chlorine levels higher than I have been in the past.

The pool store guy was talking and talking and talking about phosphate levels though. Having been here for awhile and absorbing everything....what the heck are phosphate levels? Sounds like the newest pool store money making scheme to me. He also looked at me funny when I told him I use WalMart bleach for chlorination. :)

If I understand it correctly, the deal with phosphates is that they are food for the algae and the idea is to reduce the food and starve em. Pffft, quicker, cheaper and easier to just kill the algae with chlorine instead of adding another chemical to the soup. If algae is growing your sanitation level is too low for everything else anyway.

LOL. If the pool store asks about chlorine, I tell them I use sodium hypoclorite. Most stores know prefectly well bleach is a lower concentrate of the same stuff they sell.

Update!

Thanks to you folks, I think my issue was with sanitation vs. cleaning ability. I shocked to 20 ppm (highest I've EVER gone in my pool) and now hold the chlorine between 5-10 and all is well. Chlorine level seems to drop about 5 ppm/day though, which seems kinda high???

My pool has been crystal clear for a week now and I think I just need to keep it at/above 5ppm now. Previously though.... 3 ppm used to be good for a non-green pool, but I guess maybe my stabilizer levels were lower in previous years.

That does seem high; you may still have some lingering algae that's consuming your chlorine.

(I'm begining to think that I'm Matt4X4's PR man)
There is apparently a type of algae out there that develops this time of year and is a persistent bugger. Matt posted today on it, and how he treats it, successfully. Here's the link, http://www.poolforum.com/pf2/showthread.php?t=5612.
(I've put this link on 3 threads now - which should help explain the intro)
I think that we all owe Matt some kudos for identifying this problem as algae, I looked at the picture linked to above and said "filter blow-by :o ".

Reading this thread from top to bottom is another example of what seems 90% of water quality issues posted on this forum over the years.....LACK OF CHLORINE.

Over and over, whether it gets identified correctly or not, the answer is "chlorine"................90-95% of the time.

So, when your water goes South, take a deep breath and search back to see if you have been keeping chlorine at adequate levels.....the answer is almost always "no".

P.S. Unabomber, KurtV has got a good point....5ppm daily is too much consumption. You still have organics in your water and you know the solution:) :) !

In 24 hours the chlorine level went from 7 down to 3. I think that maybe another shocking is due. I did go swimming yesterday though and the water is 100% perfect. After many agonizing weeks, my pool is finally "right" and I'm starting to actually like the damned thing again. Overseeding put lots of grass seed into the pool yesterday so I sent Billy (AKA my Aquabot Viva) to clean it all up. Though Billy was pricey....it was nice to hit one button and have him take care of it all for me. :)

I have the same problem. I have owned an above ground 33' round pool for a year. Everytime I got it blue, it would turn green in 2 days.Spent hundreds in pool chemicals. I finally, finally...changed the pool sand and added a sand cleaner. Pool was blue and stayed that way. I was very diligent on testing,chlorine levels ect. I live in south GA.

Over the winter my electric line was cut. No pump for a week.Pool was greener that green. Took me a week with chemicals no my pool is blue. BUT, My filter is still blowing out green. I changed the sand twice! The green is not as dark as it was, but it is noticable. It will blow out green for a second then blue. I use both the backwash and rince cycles. I have been putting a hose when I 1st start the filter back up, in front of the blow out to get rid of the green. I put CYA last season, I think I need to put some more.

Pool hold aprox 25,000 gallons water and pump takes 4- 50lb bags.

Does anyone have any other ideas?

Thanks,

Lisa

HI Lisa, sounds like you have to post some numbers

FC, TC, CC, CYA, pH?

Yes, you must post numbers. You cannot fix a sick pool without testing the water.

You're going to need to keep your free chlorine at shock levels, maybe for as long as two weeks. If it drops you will back to square one. You cannot do that without a proper test kit.

We have lots of stickied threads on how to do this. Please read them.

Hello,
I had taken my water sample down to the pool place. They said all my levels where fine. But, I may want to increase my chlorine level and to get some CYA. So I did that yeasterday.

Before putting that all in, the green in my return has gotton worse and the pressure in my pump is now down to 5 where it was up to 9 or 10 2 days ago.

I am getting new gaskets, where the clean out is, if you turn it just a little the pressure goes up??? I think from changing the sand a couple of times already the gaskets may be bad. I am going get new gaskets, more sand, the Aquachem sand cleaner and DE?, I think it is called to increase pressure. I hope this works. I am getting fustrated. Although, my pool is still clear, Thank you Lord!!!! If I don't ask fast it won't be.

Do you have any other suggestions?

Thanks a Bunch,

Lisa