Sparkling again... finally

[rodrigo]

I'd posted a couple weeks back about a problem with water that remained stubbornly cloudy, despite good, healthy, balanced numbers. I got the advice to examine for filtration issues. I thought I'd share the success story in case it helps anyone else out there...

I'm using a 200# Hayward top valve sand filter, which I switched from sand to Zeobrite at the start of the 2009 season. Was very happy with the filtration results last year, but noticed that my pressure did not increase over time the way it did with sand. As a consequence, I rarely backwashed... which I think may have been part of the problem. My bather load is not terribly heavy, and the automatic cover is usually only rolled back when the pool is in use.

The project unfolded over the course of several days. At the very start, I thoroughly backwashed, and then popped the top off the filter. Despite backwashing, there was as very surprising amount of junk on top of the media. I started rising the Zeo inside the filter with a garden hose, filling it up and letting it overflow over the top. I was able to rinse a fair amount of funky brown stuff out of the filter this way, but it was an incredibly tedious, time-consuming process that wasted a lot of water. After spending a few hours over the course of a couple of days messing around this way, I concluded this was a poor use of my time (I already knew I could dump the Zeo and go to fresh sand for about $35). I decided to give it one more try to fix this, and to do so mostly in the name of science (and also in keeping this nearly-new, expensive Zeobrite out of the landfill). I needed a nuclear option.

I came across this article about regenerating Zeolite annually on the mfr website:
http://www.zeobrite.com/PDF/Zeobrite%20 ... cedure.pdf

I devised my own procedure that combined the above with a media remove/wash/replace process. So at 1:00 pm Friday, I began draining the filter and scooping out the media into a wheelbarrow lined with landscape fabric. Once empty, I removed the stand tube/lateral assembly. I carefully washed it all (even scrubbed the laterals clean with a soft vegetable scrubbing brush) and examined laterals for any sign of cracks or breakage. All the hardware checked out.

I fashioned a wash filter out of a second piece of landscape fabric and some zip ties. I began the process of moving small batches of the media into the wash filter and rinsing it out with fresh water from the hose (envision a giant tea bag), until the water ran nearly clear (completely clear took a lot more time & water -- and I was going to follow up with the regenerative procedure anyway). These batches went back in to the filter container (which had the sparkling clean lateral assembly reinstalled and had been filled halfway with fresh water. After reloading the media into the filter, the water inside looked surprisingly cloudy. I mixed up my regenerative solution according to the Zeobrte instructions above (salt + water + filter bed cleaner), and put all into the filter. This process was completed around 3:00 pm (elapsed time: 2 hours).

I let the solution soak in the media for about 4.5 hours. So around 7:30 pm, I buttoned the filter back up and backwashed the mess inside to waste. After the glass ran clear, I rinsed the valve, and then backwashed again (per the instructions above). So by 8:00, I was filtering again as normal. I closed up the automatic cover and went inside to enjoy a beverage and change channels.

Interestingly, after all this rinsing and cleaning, my 'fresh' psi stayed at 17, exactly where it was before I started. Really, where it always is. Since going to Zeo, my pressure virtually never changes.

We went out of town Saturday. So upon returning home Sunday afternoon, I rushed out back and rolled back the cover. And there she was, in all her glory. The sparkle had returned.

I think the most important lesson I'm taking from all this is to not wait until I have an appreciable increase in pressure before backwashing. The 3 - 4 psi increase was a great rule of thumb with sand... but for some reason it does not seem to apply to my system with Zeo. I probably will also make the regenerative process an annual exercise (skipping the remove/wash/replace bit... that kind of sucked). The next couple of years will determine whether I stay with Zeo or go back to sand.

Thanks all, for the help & support.

 

[JasonLion]

Thank you for sharing your story and for writing it up so throughly!

The last time regenerating came up, the general consensus was that it wasn't worth doing, since it really only helps for a couple of days before the media gets saturated.

 

[rodrigo]

That's one of the downsides of my hybrid approach. I really don't know what fixed the problem -- the thorough media wash or the regeneration procedure. Maybe they both played a part.

However, I did conclude that lots of backwashing over a short time span will not make up for neglecting the process over a long time span. That Zeo really likes to hang stubbornly on to its funk.

 

[Melt In The Sun]

rodrigo, any chance your pressure gauge is broken? It seems strange that your pressure never increases.

 

[duraleigh]

Rodrigo,

That's a great post. Thanks for explaining you story so carefully. That will be a benefit to the many zeo users here on the forum.

 

[rodrigo]

Thanks, gents!

I did wonder about the accuracy of my gauge at first, but it seems to behave normally. When I power the pump down, it drops immediately to zero. It also reflects diffferent pressure values when I switch the intake valve between main & skimmer -- as well as when I ran the barracuda.

It's really weird. I could go for a month without backwashing, using the barracuda twice a week, and I wouldn't be able to discern a difference in psi (beyond the situations I mentioned before).

 

[chem geek]

It should be noted that the Zeobrite® procedure is combining two different things into one procedure: regeneration and cleaning. Regeneration removes ammonium ions from the zeolite replacing them with sodium ions from salt. This is not necessary to do since there will be virtually no ammonia caught by the zeolite since properly maintaining chlorine in the pool will have chlorine very quickly (less than a minute) combine with ammonia to from monochloramine and then get full oxidized to nitrogen gas in a few hours. Zeolite will not remove monochloramine. Therefore, their implied claim that ammonia removal will prevent monochloramine formation is bogus (the rate of formation of ammonia from monochloramine is slow so that the filter does not effectively remove monochloramine).

About the only time I could see zeolite's removal of ammonia being useful is if there were a bacterial conversion of CYA into ammonia when a pool is "let go" with zero FC levels. Then, the filter could remove the ammonia instead of having to use lots of chlorine to do so.

Cleaning, on the other hand, is important so that the filter media can catch additional material. It is unfortunate that backwashing is not able to remove the organic material and that cleaning is required, but that's part of the maintenance tradeoff vs. smaller particle filtering that you will have to decide whether it is worth doing.

 

[Terry]

I have had almost the exact same experience and Zeosand since 2007. My pressure gauge never rises, though it does change when moving between skimmer, main drain, spa, and to zero when off.

I opened my filter yesterday and was amazed at the amount of junk in the filter. I spent 2 hours with the hose inside the filter overflowing junk out the top. As soon as I’d think I was just about finished I’d swirl the sand with my hand and more junk would come out. Granted, I’ve had the zeosand in there for 3 years, but with the amount that came out you’d think I’d never backwashed. I finally gave up after 2 hours for fear that I would never be able to stand upright again if I kept going. I then drained the water from the filter last night and can't belive the amount of junk still sitting on the top of the sand today.

I'm having trouble with the zeosand ending up in the pool through the return jets. I haven't decided yet if I think the zeosand is breaking down into smaller pieces with age, or if it's just the naturally occurring smaller pieces that are getting though the system. The pieces I'm collecting in the pantyhose over the return jets are definitely smaller than the sample I pulled out of the filter.

Curious, what color is your zeosand? Mine is green. The mfg is telling me that some of the grey zeolites will break down, but their green sand (different quarry) does not. Do you ever end up with zeosand in your pool?

Another thought, does your Zeosand take up as much volume in your filter as the sand did? I used the recommended 1/2 the weight, but it does not come up as high as the sand did in the filter. Hayward says the sand should come to within 6" of the top of my filter, the zeosand is 16" below. I wonder if this could be preventing an effective backwash.

 

[rodrigo]

I opened my filter yesterday and was amazed at the amount of junk in the filter. I spent 2 hours with the hose inside the filter overflowing junk out the top. As soon as I’d think I was just about finished I’d swirl the sand with my hand and more junk would come out. Granted, I’ve had the zeosand in there for 3 years, but with the amount that came out you’d think I’d never backwashed. I finally gave up after 2 hours for fear that I would never be able to stand upright again if I kept going. I then drained the water from the filter last night and can't belive the amount of junk still sitting on the top of the sand today.

This is exactly what I encountered! The endless stream of dirt & junk in the media was the driver behind my decision to pull the stuff out of the filter and wash by hand.

I'm having trouble with the zeosand ending up in the pool through the return jets. I haven't decided yet if I think the zeosand is breaking down into smaller pieces with age, or if it's just the naturally occurring smaller pieces that are getting though the system. The pieces I'm collecting in the pantyhose over the return jets are definitely smaller than the sample I pulled out of the filter.

I typically find a very fine, sandy-colored substance accumulated in the nooks & crannies of the pool; steps, corners, etc. I always assumed it was dust & dirt that found its way in from the surface. When I realized I had a filtration problem, I wondered if this was really small bits of the media. I've heard that getting filter media returned to your pool was an indicator of of a broken lateral. That was another big reason for pulling out the Zeo - so I could inspect the laterals for damage.

Curious, what color is your zeosand? Mine is green. The mfg is telling me that some of the grey zeolites will break down, but their green sand (different quarry) does not. Do you ever end up with zeosand in your pool?

My zeo is not green, so I guess it's gray? When I pulled it out of the fliter, the damp zeolite was... we'll call it khaki. After I rinsed it through my landscape fabric rig, the damp zeo was several shades lighter.

Another thought, does your Zeosand take up as much volume in your filter as the sand did? I used the recommended 1/2 the weight, but it does not come up as high as the sand did in the filter. Hayward says the sand should come to within 6" of the top of my filter, the zeosand is 16" below. I wonder if this could be preventing an effective backwash.

I got the same formula from the place I bought my zeo (4 bags of sand = 4 bags of zeo, even though a bag of sand is 50 pounds, and the zeo considerably less, maybe 25? I don't recall). But the volume is significantly lower, similar to yours. On a side note, I noticed that when I backwash with zeo I see much more media swirlilng in the sight glass than I had sand. I wonder how much of it I am losing out the backwash line...

Also, I wonder if I compounded my problem by using a barracuda? I'm experimenting with a friend's Blue Diamond robot to see if I can keep some of that junk out of the filter from the outset. My friends sold the house that had the pool, but didn't leave the unit for the new owners (gave them a barracuda instead). I might be able to pick it up for a good price... If I like it... which I think I do...

At this point, I can't really say whether I will stick with zeolite when the time comes to replace it. I was romanced by the suggestion that it can filter much smaller particles, but wonder if I will constantly be battling these saturation issues. I wasn't unhappy with sand...

 

[phatocaster]

I have been battling a green pool all year. Haven't even swimmed in it yet. I have been added lots of bleach for the past two months and still green. The only think I changed this year was I switched to Zeo Sand. I read to pour chlorine in the filter and take a pvc pipe and stir the Zeo around in the filter being careful not to damage anything. Then backwash and rinse several times letting it settle in between. I'm going to do something even more miraculous. I getting this junk out of my filter and going back to good ole sand. I can only speak about my experience, but Zeo Sand is junk. I took a test sample to the pool store just to see what they said. They told me I had high level of chlorine and to not swim in it. Everything else was dead on. He said it was a filtering problem. I told him I switched to Zeo Sand. He just laughed. He said I have had a pool for 30 years and I have changed my sand maybe 6 times. He said go with sand. Amazing...A pool store that doesn't try to rip you off. He told me his reputation meant more to him than selling Witch Doctor Remedies for pools. So if anyone wants Zoe Sand I will pass it along free of charge. Just come and get it.

 

[SPP]

Hi Rod,

Chem Geek is probably correct on the zelbrite/zeobrite not able to do the ammonia thingy as well as claimed.
He is like Einstein of chemicals and the TFP forum won't be as advance as this without our Master Yoda

I started using Zelbrite ( Australian source ) to replace sand in my Hayward in 2007.
Aside from ammonia thingy, there is some actual advantage of my Zelbrite, it is in some way porous down to a claimed 3 micron, totally unlike sand which does the cleaning using friction of I-squeeze-u-****-dirt-between-sand-grains method......

This 3 micron capability is surely not a 100% efficiency, I think at best 60ish percent and plus the mechanical properties of the Zelbrite itself being like a sand filter, to whatever tune of efficiency. However if anyone ask me is Zelbrite superior compared to sand for its filtration power.........answer is YES. However, you can't get superb water clarity with just a sand filter. I rigged mine with a 20 micron Hayward cartridge filter downstream of the Zelbrite.

Being with pores that small the Zelbrite has, backwash can't really clean them trapped ( I think adsorb is a better word ) particles well. Your method of cleaning Zelbrite does make sense and I would to try that one day, thanks for the experiment.

Eventually we need to throw the Zelbrite away and get new one. Like cartridge filter, there is only so much trapped particles you can wash off and eventually a new one is a must. For me once a year is my schedule.

Below is a year 2007 zelbrite inside the Hayward
[attachment=2:1mz2j30v]Zelbrite of year 2007 - inside sand filter housing.JPG[/attachment:1mz2j30v]


Below is when my staff took it out, ready for disposal
[attachment=1:1mz2j30v]Zelbrite of year 2007.JPG[/attachment:1mz2j30v]


Below is new Zelbrite of Feb 2012
[attachment=0:1mz2j30v]Zelbrite - New 2012.JPG[/attachment:1mz2j30v]

My staff ripped open the Hayward sand filter middle pipes and its legs and clean them all.


If one expects Zelbrite or sand alone to do magic......you won't get it.
The beta ratio is what defines what particles can be trapped by the media chosen at what efficiency. This I learn for my work with diesel engine filtration and it can be applied to pool, same same....we want to catch particles.

Sand type filter , is at the bottom of the scale.
Zelbrite as sand is a mix efficiency.
Cartridge filter is better than sand but I do not know their beta ratio.
Some Lab filters are rated as absolute, but if we use this in our pool, I think we go broke fast...

Human vision supposedly can see down to 50 microns. Smoke from cigarette is much smaller but due to its light bending properties, we can see it clearly. Sand filters squeeze the dirt method won,t get us <50 microns capability. 3 microns claimed of Zelbrite but being low efficiency, in the end the output will still carry some visible particles. Need to keep the pump running 24/7 to get best benefit.

What you did is a good method of cleaning the Zeolite, same as my son when he buys new sand or small rocks for his aquarium. He washed them cleaned really well till water gets clear.

I don't have problem with pressure build up on my Zelbrite, it will always register pressure build up when contamination sets in. What I suspect is :

- Did you top up the zeo to maximum limit and packed them well ?
A loose packed zeo will allow easy passing of water and hence less resistance to register clogging and at the same time zeo being lighter in specific gravity compared to sand, its squeeze the dirt method wont work well when they are not packed well.

I don't know what is the specific gravity of your zeo brand compared to mine as I never have problem since day 1 in 2007 as far as registering pressure built up. I get dirt trapped within 7 days when low swimmer load and as soon as 3 days with higher swimmer load.

I also think zeo will work better in a bigger filter size and depth bed, given that their specific gravity is lighter than sand, at least water pressure can't push away too much zeo if the bed depth is plenty.
I can't remember my filter size or model but its not too small.

Good luck with your pool........... and glad you got it sparkling clean again.
.