So, i added some DE to my sand filter. Ugh!

[NHfloater]

Hi, folks. After vacuuming my pool to perfection, mask and snorkel style, I backwashed my filter. Not being satisfied with my freshly cleaned pool, I added 1 cup of DE (1/2C at a time) to my skimmer, and watched the pressure gauge. Starting pressure was 15psi. After 1/2C of DE, still 15psi. I waited about 5 min and added another 1/2C. No change on the pressure. Wait, what's that catching my eye by the return? It's DE! Cool

Now, as you know, my water is cloudy, bad. I searched online and found the usual culprit is a filter issue, be it cracked laterals, sand deficiency/channeling, or a gasket issue. My filter is 1 month old. I saw the installer carefully pour the sand into the filter, using the supplied deflector thingy. I'm not sure the quantity but I think it was 150#'s. It does not leak and has done a fine job thus far.

I called the pool store and they gave me the likely reason this happened, at least in their opinion. They said to clear it up, run the filter 24/7 for a few days.

Before I reveal their answer, do you guys have any suggestions?

 

[Patrick_B]

My opinion is you have a problem. Likely one you already mentioned. DE should not be passing through the SF.

 

[NHfloater]

I should've added, I forgot to hit the rinse setting after backwashing.

The pool company seems to think it was due to the lack of settling time between back washing and adding the DE, as well as not rinsing. They seem to think the sand being loose caused the DE to go right through the sand and into the pool. This also explains the lack of pressure increase. They said if the gasket was bad or the laterals were cracked, I'd likely have leaks or sand coming out of the filter.

Hopefully, this was caused by my rookie mistake and not something else.

 

[NHfloater]

Patrick, is there something I could easily check right now? I've never taken the valve off but I'm fairly handy. Hopefully this has nothing to do with the laterals as I really don't feel like breaking out the shop vac and making a mess.

Do you think the pool company's explanation is plausible?

 

[duraleigh]

I forgot to hit the rinse setting after backwashing.

By not rinsing, you did not allow the DE to embed back into the sand and simply pumped it back into your pool. I think it will clear on it's own.

If you had no problems prior to adding the DE, it would be a leap to think you have any mechanical problems now.

 

[NHfloater]

Well the DE was added AFTER the backwash, and nonexistent rinse cycle, but I get what you're saying and agree. Logically, it makes sense. Hopefully it clears up.

Does a day or two sound like a reasonable time to expect the DE to find it's way back into the filter? I think there's plenty of turbulence to keep it from settling on the bottom.

 

[Patrick_B]

For what is suspended probably yes. I would surely think some will settle.

 

[NHfloater]

Thanks, Patrick and Dave.

I'll keep you posted as to the results.

 

[NHfloater]

I added clarifier last night. This AM the water was clear again and the pool bottom had DE all over it. Just for the heck of it, I added another 1/2C of DE, thinking if the sand bed not being settled was the issue, surely 18 hours of the pump running would've settled it. Anyway, the DE blew right through again.

I called the pool store and spoke with the same person, who seemed pretty knowledgeable, but was not one of their techs. Again she said if the laterals were cracked/damaged, I'd be getting sand in the pool as well, which I'm not. No leaks, no sand, etc. Pump/filter operating normally with no DE.

Not sure what to do/check at this point. All their techs are off today. I'm in no great rush to fix it but I'd like to avoid the service call and mileage as they're 30 miles away in a different state. Even if it ends up being a warranty issue, I still think they charge for labor, or at least the service call and mileage.

Is there anything I can check on my own? Any suggestions?

ETA- Is it possible my filter sand is too "new"? I've used the pool a whole 7 times since Aug 1st. At no point has the head pressure risen over the base clean (brand new) pressure of 15psi. In other words, is it possible my sand is TOO clean and fresh and that's what's causing the issue. Like I said, the pool is relatively barely used and there hasn't been much debris, tree, body or otherwise, in the water.

 

[duraleigh]

I guess my thoughts would be if you stopped adding DE and clarifier would your pool be fine?

 

[Smykowski]

Did you ever check the spider gasket and standpipe? DE blowing out that fast means that it is bypassing the sand altogether.

 

[NHfloater]

Seems that way, lol. I did as much research as I could and found nothing but positive experiences with pool owners that did this "trick". I figured I'd give it a shot in hopes of getting super clear water, particularly at night. I should've just left it alone.

 

[duraleigh]

My nine year old sand filter has never had anything in it but sand....still the original.

My water is about as clear as it gets.

 

[NHfloater]

Thanks, Dave. Once I get this DE out, that's it. Sand from here on in.

At this point I'm trying to figure out the best way to remove it. Vac to waste, logically, is probably the best solution. Unfortunately I see about a half hour of slow vacuuming in my future and I'm on softened well water. 70 GPM for 30 min= Ya, not the best thing for my softener. The well has plenty of recovery. I'm not worried about that.

My other idea, and I know it ain't gonna be popular here, is to add a flocculant in hopes the sand filter will pick up the particles and hold them long enough til I'm done and can backwash the filter. Obviously, the downside is it might not work and I'm going to be out $ for the floc and the time spent fartin around with it.

Its supposed to pour out today so I'm headed out in a half hour or so to use option 1 and let the rain replenish some of the 2100 gal I'm about to lose. If anyone thinks there's a very good chance the floc option will work, please, chime in now.

 

[duraleigh]

Before you waste that water, it is not clear to us on that you have taken the top off the multiport and inspected the spider gasket......did you do that?

 

[NHfloater]

No, not yet. I vacuumed to waste for around 5 min and got some of it out. The stuff turned to dust again immediately upon contact with the brush, so I'm not even sure how much actually left the pool.

But wait, the story gets better!!!!...and I think I found the root of the evil. Laterals?..prob not. Gasket?..prob not. EDIT- DE(HOPEFULLY) But why? Read on, for the highly embarrassing answer.

I went to my local AGWAY (farm and garden supply store) to get my DE. You gurus see where this is going yet? "Hello sir, yes, we have 2 kinds of DE. One is food grade, one is for pool water" I asked if DE is DE. "I believe so, sir, it's just powdered diatoms" "How much ya need?" I told him I only needed a couple cups. "Well the pool stuff is 25 lbs, but we have 4 lb bags of food grade stuff over here." OK, I'll take the food grade stuff, seeing it's all the same.

Apparently, WRONG!!!!

As you guys prob already know, the main difference is particle size. Pool DE is relatively MUCH larger. This is likely the reason the food grade stuff blew right through the sand. I have no idea what the texture of pool DE is supposed to have, but the food grade makes drywall dust feel like gravel. It's insanely fine. I failed to see the fact the 25#'s of pool stuff was close in container size to the 4#'s of food grade stuff. IDIOT!!!

Anyway, unless you guys say otherwise, I think my only choice is to use an actual flocculant to get this food grade stuff out. I'm actually thinking about putting official POOL DE in to aid in the battle, otherwise it's gonna take a LOT of vacumming to waste to get this junk out. Never having used a flocculant, I'm not sure how well it would work. Pool DE in filter, flocculant, vacuum and backwash, repeating the process for a few days, is my plan.

Any suggestions?

...and, yes, I realize I'm an idiot

 

[Patrick_B]

I'm only familiar with filter grade for pools/aquariums, and gardening grade for soil amendment. If food grade is that much finer, it must be really small in particle size. I still can't suggest the floc without knowing what it will do, but it's your pool. You may get lucky and have it work, but just know you may not. If it does work, there is a chance it will cause a huge need for frequent backwash, so be aware. Don't beat yourself up too much, we've all paid some stupid tax along the way. Good luck, and let us know how it works out.

 

[duraleigh]

I'm not convinced. Using floc and more DE sounds like more of the same that got you where you are to begin with.

Your pool, your decision, I would open up the multiport.....but maybe your way will work.

 

[NHfloater]

Thanks, Patrick and Dave. I've found minimal info online regarding the difference between food and pool grade DE. Searching for DE on Wiki, is where I found the initial info on particle size. I found a few other tidbits of info, with one in particular regarding a company's food grade DE having particle sizes of approx 10 microns, surely fine enough to get through the sand bed.

I concede I have very limited knowledge of the components/mechanics of a pool filter, and I respect what you guys are saying. I'm just confused as to why the filter performs normally, in my eyes, to allowing DE to pass straight through. Like I said, I've never seen sand anywhere in the pool, which I believe is an indicator of at least a lateral issue.

First thing will be to check the gasket, and who knows, maybe I'll see other issues. If that's good, the next step is cleaning the pool. I'm gonna skip the addition of pool DE for the clean up of what's in there, but I just don't think I can get by without a flocculant. What's in there is simply too fine to vacuum without it. It would be like trying to sweep Styrofoam peanuts in a hurricane.

Again, I'll keep you posted and have no problem coming back with my tail between my legs if the DE wasn't the issue, and that wouldn't surprise me one bit if it was filter related. That would be par for the course for this install.

 

[Patrick_B]

What's in there is simply too fine to vacuum without it. It would be like trying to sweep Styrofoam peanuts in a hurricane.

That provoked a vivid image. I have a hard time getting them all into the trash without losing a few. Blasted things! :lol: