curb1, I am not an expert however I understand that sand is good for about 10yrs. (Hope I am correct :) )
I would open the pool, run the pump and see if it is filtering correctly. Our pressure runs about 18psi on clean sand and we have a S220 pro series Hayward sand filter. Hope this helps.....

It is recommended by most sand filter manufacturers to change the sand every 3 to 5 years. It is true that the sand may last up to 10 years but the sand tends to break down to the point of not filtering properly after about 5 years. Yes you can just change the sand on your filter. I recommend changing the laterals at the same time. Last thing you want to do is change the sand and then find out that you have a busted lateral after you have added the new sand. If you do elect to change the sand try using Zeo Brite sand it will filter finer and last longer also you will not have to use as much of this sand in your filter.

Fighing irish, thank you for correcting me as I am new to this. I will have to remember next 3-5 yrs to use Zeo Brite sand. Do you think my pressure will increase using the finer sand?

Thank you for the comments. We'll see how it goes. The "pool guy" recommended changing the filter (not the sand, but the whole filter) every year. That didn't sound good.

Zeo brite does not last longer than sand. The volume of the zeobrite is the same, its the weight that is different.

Sand has a somewhat indefinite lifespan. The "rounding" people have claim to see is not as common as we are led to believe. There are 30 year old pools with no work that has ever been done to the sand filter, and the pools still look incredible. There are several factors that come into to play, but typically in a residential pool (absent the use of biguanide products), the filter will break before the sand "needs" to be replaced. Especially if you are maintaining it properly with degreasers, and de-scaling agents.

Thank you racket for your info. My pb suggested sand because he told me that it would be easier than DE or the cartridge filter. So far I am pleased with his suggestion. My pb has a sand filter for his personal pool and he has no problems with it.

We have never used Zeo brite, but totally agree with rackets second paragraph. The sand in my filter is 22 years old and working fine. Never used a degreaser or de-scaler. The only time I have seen laterals wear out is when the filter was hooked up backwards by using a DE multiport valve.

Not sure where you guys are working on pools. But here I run into sand filter issues all the time. Now this is primarily on larger commercial pools using Neptune Benson and/or Astral filters but I have seen it in residential as well. Especially the worming effect that you get from years of neglect. And as far as laterals are concerned. They become brittle over time just like any other peice of plastic does. and being as the only cost about $6 piece I think it is a worth while investment to replace them at the time of sand change. I don't know how many time I have seen a DIYer change the sand out and crack a lateral going back in with sand. Now that being said most of the time it is improper installation of the sand (meaning lack of water in the filter at time of sand installation) But I have also seen it happen to a brittle lateral as well.

Thanks,

David

The 1995 edition of Purex/Triton Hydraulics and Filtration refers to the media in sand filters as "Permanent (15-20 yrs)" and also states that if the sand gets plugged to remove and replace the top 1 inch of sand and chemically clean the entire sand bed.

Thats the latest edition I could find but don't think sand has changed much since then. I am unaware of a filter manufacturer that reccomends changing the sand every 3-5 years.

The worming or channelling is quite often a result of the clogged bed.

This from the Hayward website. Found it yesterday.

When do I need to replace my sand?

On average, sand should be replaced every 3-5 years. This may be longer if the pool stays clear, or shorter, if the filter runs all the time. The jagged edges of the sand wear down and become smooth as the sand ages. When this happens the sand can no longer trap debris particles and dirt can pass through the sand and back into the pool.
If the pool is chemically balanced, the system is running the proper length of time and the bather load is normal, but the water will not clear, even using a flocculant or clarifier, then the sand needs changing.
As the sand ages, it may start to clump and the water flow can form channels in the sand, allowing the debris to pass through. Channeling is often seen when the pump horsepower is too large and wants to move too much water through the filter.

http://www.haywardnet.com/contactus/faqs/viewfaqs.cfm?category=3&subcategory=23

"Now this is primarily on larger commercial pools using Neptune Benson and/or Astral filters"

That is why I said " in a residential pool"

Everything is different in a commercial enviroment.

Issues caused by sand in residential pools is very rare. Channeling can happen, but with proper backwash flow rates, and reasonable bather loads is very rare.

Curb 1 all any sand filter is, is a tank that holds sand and water that has laterals that keep the sand from getting back into the pool.

I am not sure why they say every 3-5 years, I think that is a little much unless it's a commercial filter.

Now this is why I enjoy this forum. Here we have two or more pool professionals with two different opinions and or solutions. I like the debates that do happen here and no matter what the outcome. This allows a person tring to fix the problem several different options. In this business the more knowledge you gain the more successful you become. So, in this being said (CURB1) you have a few options here. And I do think the the popular agreement here is that you do not have to replace the filter. Only to either chemically clean or change the sand. Hope everyone agrees. Thanks and good luck.

David

This is good forum with a wide variety of opinions based upon a wide range of experience. What seemed to be a fairly simple question obviously doesn't have a simple answer. I looked for some scientific evidence that might have a pat answer and found none. You would think that sand filter manufacturers would have the same answer for this basic question but that is not the case.

This is what I have deduced from the discussion and personal experience.

1. Commercial sand filters require more maintainence. a.Most commercial pools are built to minimum standards and flow rates.
b. Most commercial pools are backwashed on a time schedule rather than a pressure increase.
a+b = more frequent backwashing.

I believe that the majority of rounding of sand/silica/quartz particles occurs during the backwash cycle when the sand is tumbled rather than water erosion during the filtration cycle.

Therefore, bigger is better!

Well put. I agree 100%. And after looking back at the original post and the follow up comments.

quote
"Thank you for the comments. We'll see how it goes. The "pool guy" recommended changing the filter (not the sand, but the whole filter) every year. That didn't sound good."

This information is very incorrect.

Your sand filter body itself probably has many, many years of life left in it.

The "pool guy" is tring to get you to spend money you do not need to spend.

Thanks,

David

I thank all of you for your comments. I have learned a lot from this discussion. I will tackle this project when we open the pool in the Spring. I know the sand will be an issue since it has been shut down for about a year.

Thank you.

OK, you've heard from some "pool experts" - now you'll hear from a homeowner who has a sand filter with Zeobrite.

Our filter is a Sta-Rite System 3 High Rate Sand Filter, model S8S70. If we were to use pool filter sand in it, it would take 300 lbs. Since we use Zeobrite, it takes 150 lbs. As was stated above, the volume is the same, but the Zeobrite weighs half of what sand weighs.

If anyone were to use sand or Zeobrite in a sand filter, when first adding the filter media you should fill it about half-way with water. This eliminates stress on the laterals to avoid breaking them.

Whether you use sand or Zeobrite, the filter media should be cleaned once each year. All pool supply stores carry several different products that can be used. Essentially, you should backwash the filter, then you put it back into the filtering mode. With the filter running, pour the cleaning solution into the skimmer so that it is "sucked" into the filter. As soon as it's in (it will be fast), turn the filter OFF. (Or, you can take the lid off the filter pump and pour the stuff in -- this, of course, is with the pump OFF.) Let the stuff soak for 24 hours, then backwash until the water runs clear (it may be foamy at first). If you do use Zeobrite, there are special cleaning solutions for it -- One is called Ultimate Clean and Refresh by Advantis Technologies. The other is called Zeo Filter Cleaner made by Biodex. Some folks may tell you that Zeobrite needs to be "regenerated" every year, but per the company, that applies generally to commercial pools only, not to residential pools.

Zeobrite can filter impurities down to 3 microns in size - the same as DE. The DE is a very fine powder and you have to exercise extreme caution when adding it through your skimmer because you do NOT want to breathe any of it in - it's a known carcinogen. Also, most municipalities have restrictions on the disposal of DE, so you can't just backwash a DE filter so that the water runs anywhere.

Zeobrite, on the other hand, does not present any disposal issues when it does become time (or just because you want) to change it out. You can mix it into your planter areas, or spread it out over your lawn. Most folks have seen or heard of a product called Turf-Aid. It's a Zeobrite product.

Our pool was built in 2004, and we've used Zeobrite since the very first day. We love it. Our water is so clear that it sparkles. Everyone who has been in the pool, or even just in the backyard without going into the pool, has commented on how great the water looks.

Nothing beats a "sand" filter for ease of use and maintenance. And Zeobrite is the best filter media you can use in it.

There is the absolute answer right off the Zeobrite website.

I guess that i need to call all of our customers that havn't cleaned or changed thier sand in 20 years and tell them the filters can't be working.

Renovxpt, are you insinuating that my post was "right off the Zeobrite website"? If so, you are absolutely incorrect. Check my page - I've been posting here since May 29, 2004. (You've been here for less than one year.) Check the archives - I've posted about Zeobrite many times; and about how much we like it and wouldn't use anything else.

Do we clean our Zeobrite every year? No. But our pool doesn't see as much "action" as a pool at a home with kids. The purpose of cleaning the media, whether it be sand or Zeobrite, is to remove a buildup of oils. If you've got a bunch of folks with suntan lotions/oils in your pool, you'll have a greater buildup of oils than a pool used by folks who don't grease up before going in.

Lindsey, Please accept my apology for the tone of that post. You have every right to share your enthusiasm about Zeobrite and as previously stated I have no experience or opinion about the product.

Its been my experience that a properly sized sand filter with simple filter sand can last decades with little or no maintainence. I have many customers to substantiate this claim. We also have had great experience with properly sized DE filters. It is not my intention to endorse any particular product. I am simply defending a time tested and very basic filtration process.

Apology accepted. :-)

I read somewhere that you could add DE to a sand filter and you would get better filtration. Anyone ever heard of that and if so what would be the process for Hayward pro series sand filter model S220T?
Thanks in advance

Adding DE to a sand filter is done to simply help clear out some particles that are seemingly too small for the sand bed to capture.

An S220 would take about 3/4 of a lb to the skimmer, slowly so as not to create a clump or clog, to create a thin layer on top of the sand bed. Larger filters would get more, smaller, less. Backwash after the pressure goes up in the tank 5-10 PSI from normal.

I only do it as a last resort. I prefer clarifier.

Scott

Thanks Scott, I think that our pool looks pretty clear or maybe my eyesight is getting bad :) I sometimes see small particles in the water but the pool looks crystal clear. I plan to use the BBB method as soon as the plaster is fully cured. It is only about 5-6 mths old.

If the lights are on and you see little specks in the water and you have a sand filter, the use of clarifier will clear the specks.

Scott

Thanks Scott, I will try that as soon as we get warmer weather. It have been very cold with temps in the mid 20's for 10-14hrs at night for the last 10days. This is very unusual for Jacksonville. We have 4 more days left till we start to see 60's in the day which is normal.

I can tell you now that Lindsey
is the Queen of Zeobrite!!! She likes it and tells everyone about it...that's what it is all about.
Be very carefull with clarifiers in a sand filter add only what the directions call for or you could make matters worse. By gumming up the sand and allowing everything to pass threw the filter.

Gosh, Muddy, I remember when you posted that I gave such accurate information regarding pool-related stuff (not just filters) that you posted an online job offer to me.

I guess I don't quite understand the tone of this most recent post of yours...

Sounds like the best thing for me to do is nothing. The water seems pretty clear and I do not want to add things that will cause me a headache in the long run........

BrentR - one thing you can do, which won't cause any headaches - is to buy a product called PurFiber. It's added through the skimmer. It ends up sitting on top of the sand and will increase the efficiency of the sand's filtering ability. And when you backwash, the stuff is backwashed out. It is a nontoxic cellulose product.

PurFiber is a DE alternative.

Scott

It's a DE alternative, but it can be used with a sand filter, too (even a sand filter with Zeobrite). :-)

First, I apologize for my misspelling of the product name - it's Purifiber.

OK, I'll link to the product Instruction page on the product web site, but here's a quote: To enchance pool clarity with a sand filter, add 4 oz. (2 cups) of Purifiber for every 50lbs. of sand contained in the filter. Reduce flow. Allow pump to circulate to achieve several pool water turnovers or until water clarity is achieved. After pool water is clear and/or the sand filter backwash is indicated, back flow the sand filter to remove dirt, debris and dirty Purifiber.

Here is a link that might be useful: Purifiber instructions (page 2)

Lindsey
I was just kidding, It was my way of just saying Hello to ya.....Sorry if it made ya mad or anything...

Hi, Muddy!

I wasn't mad or anything... just a bit confused. :-)

Simple question? How much of a job is it to remove the existing sand from the filter (Hayward S210T)?

Depends on available work space and existing plumbing.

It could take as little as 3/4 hour or as much as 2 hours.

If the sand is dry, it helps since it's easier to vacuum out.

Scott

Thank you. We have an open area. When the weather gets better we'll give it a try.

Thanks to all - especially Lindsey - for the good info here regarding changing the filter media.

Having never done this before, I used the tips here and the document from the Zeolite Corp. website to replace the Zeobrite in my Sta-Rite filter yesterday. I ended up having to Shop-Vac all of it out as my hands and arms were too big for the opening. Other than being a bit messy (my filter and heater are inside my garage), it went quite well.

I guess I was expecting the process to be more complex than it was. I was also quite surprised at the simplicity of the inside of the filter itself. Obviously, it's the multi-port valve that is the most complex part of the unit.

Anyway, the pool is open! Thanks again folks.

Pool industry expert here - something that I feel was glossed over too much in a thread with so much other great info on sand filters is the impact of water chemistry on the longevity of sand media. If you have 1000ppm of calcium hardness becuase you use well water and you keep your pH at a cool 8.2 because you dont maintain your salt system or understand alkalinity, then your brand new filter sand will be a crystalized block of pitted silica in six months.

As with most things with swimming pools (and spas) which is the better you maintain the chemistry, the longer everything lasts.

For the question of Zeobrite, it is worth noting that there are a few alternative medias however none are approved for use by the major filter manufaturers. They will not void a warranty however they are also not tested on the product that you are buying. Silica sand and balanced chemicals are more than enough to have water as clear as clear can be. There is no substitute for strong fundamentals.

For the questions about changing filter sand you can use a wet / dry shop vac vacuum to remove the old sand. Try to find dry replacement filter sand as opposed to wet as pouring dry into the filter is SO much easiler than tyring to spoon handfulls of wet sand into the tank. Also that is great advice from a poster above and be sure to partially fill the tank with water to protect the laterals before adding the sand.

As a pool expert I am also of the opinion that sand can last almost forever. If the water is clear then the filter is fine. If you think that you are seeing sand in the pool a little too often then you may have a problem that warrants opening the filter and digging out the sand.

You should probably bookmark the link below as it is a homeowner resource for pool sand filter problems, repairs etc for laterals, changing the sand, filter head gasket failure.

Here is a link that might be useful: Pool Sand Filter Resource

As a pool professional, I am always concerned with warranties on any item that we sell and that I might share this with homeowners considering a new sand filter. Check with the manufacturer first before buying, ie. Hayward, while a quality product and one I endorse and sell (usually without qualm) has informed me today that Zeobrite (or anything other than the sand indicated in the install manual) will void the warranty. Personally, I like Zeobrite and the quality of water it provides for our customers, however, we will no longer be selling it to Hayward purchasers in order to maintain their warranties in effect.