DE in the environment

[TimS]

From all the reading I've done, it appears that adding a little DE to my sand filter will greatly reduce the smaller particulate matter. For my pool, so far, this is really only an issue at night when the light is on. (Dear daughter won't get in at night with all the "yuck" even though she'll swim in the same water in the daytime. )

I've also read the DE is considered a carcinogen. I backwash out to the yard, instead of into the sewer. Would a lawnmower blow the washed out DE around, or would it tend to sink into the ground. This is especially an issue for DW, since she gets quite paranoid about carcinogens. Do I just forget the whole thing?

Tim.

 

[duraleigh]

I have no opinion on what to do with DE but, unless this thread stays very narrowly on topic, I predict it will soon become a candidate for "Agree to Disagree" or "Hall of Lame".

 

[JohnT]

I've also read the DE is considered a carcinogen.

Where have you read that DE is a carcinogen?

DE is a naturally occuring substance. When cooked for pool use, DE assumes a crystaline form, which makes it just as dangerous as any other crystalline silica like sand. Neither is a carcinogen, but both can cause silicosis if the dust is inhaled.

Crystalline silica is used in paints, in cosmetics and as a polishing compound. It is largely inert, but causes physical irritation and scarring of the lungs if inhaled, not cancer.

 

[JasonLion]

The crystalline silica in pool DE is listed as a carcinogen, see for example this NIH document. It is normally only a problem after prolonged exposure to airborne particles. DE does not usually become airborne after being backwashed, though it is possible in theory.

Gardening DE does not have a significant amount of crystalline silica, and is not a listed carcinogen. Of course, it doesn't work very well in DE filters, so that doesn't help anything. But the existence of two different forms of DE, which are both called DE, can cause confusion when doing research on the properties of DE.

 

[zea3]

Or you can use a DE alternative, such as Fiber Clear. Works just as well if not better than DE and is considered safe for the environment. Of course, you don't want to stick your face in it and inhale it either!

 

[TimS]

...I predict it will soon become a candidate for "Agree to Disagree" or "Hall of Lame"...

Dave, isn't that true of ALL of my posts?

It is normally only a problem after prolonged exposure to airborne particles. DE does not usually become airborne after being backwashed, though it is possible in theory.

Jason, I'm less concerned about the actual risk of cancer than I am about DW's perception. My feeling is that something is likely to give me cancer anyway, so I'm not going to get too bent about it. DW however gets nervous about it. Granted, even if it did become airborne, we're not talking about very much anyway (maybe a cup per backwash?) so it probably isn't a real risk, but sometimes the reality is outweighed by the perception.

Or you can use a DE alternative, such as Fiber Clear. Works just as well if not better than DE and is considered safe for the environment. Of course, you don't want to stick your face in it and inhale it either!

Now that just might work. It would probably solve the perception problem. Have you actually used it?

It's referred to as "wood cellulose fiber." Isn't that saw dust? :lol: How much does it cost to buy 25lbs of saw dust in a pretty package?

Tim.

 

[JasonLion]

The fiber products tend to cost a bit more than DE. Neither one is usually a major expense, so this is not normally an issue.

There is also some debate about the filtering effectiveness of fiber relative to DE. Of course, the differences between fiber and DE are small. Unless you are totally focused on the best possible water clarity, you probably won't even notice the difference.

 

[zea3]

Or you can use a DE alternative, such as Fiber Clear. Works just as well if not better than DE and is considered safe for the environment. Of course, you don't want to stick your face in it and inhale it either!

Now that just might work. It would probably solve the perception problem. Have you actually used it?

It's referred to as "wood cellulose fiber." Isn't that saw dust? :lol: How much does it cost to buy 25lbs of saw dust in a pretty package?

Tim.

Yes, I have used the Fiber Clear for about a year now. It works just as well as DE in my opinion. I chose to use it for the convenience factor. It is much easier to lug around a 1 or 2 lb bag of Fiber Clear than a 25lb box of DE! It looks more like paper pulp than sawdust. White, fluffy, and very light. You have to be careful using it on a windy day! Cost is not that big a difference either.

 

[TimS]

Thanks.

I'll have to locate a source for the FiberClear, and give it a shot. DW is all about green, and DD wants the water filtered better. Unfortunately, neither of my local pool stores have ever heard of it. I guess I'll have to find an online source.

Tim.

 

[lbridges]

I don't have any first hand experience, so take this for what it's worth. Perhaps you should look into the zeobrite (or is it zeolite) sand substitute. I have read some user comments that love it, but like I said, no experience myself (previous pool was DE, next will be cartridge).

BTW, and sorry to go off on a tangent, but I've not seen DE added to cartridge filters talked about (maybe I haven't read enough?), yet Pentair's OM states, "When the cartridge element filter is used on new pools and after cleaning the elements, introduce into the system .5 pounds of diatomaceous earth per every 100 square feet of filter area, (a one-pound coffee can equals .5 pounds of diatomaceous earth). Mix the diatomite with water and pour it into the skimmer after the pump is primed and the system is operating. This will enhance the filtration of your water."

 

[JasonLion]

Some cartridge filters are fine with a little added DE, others become clogged and don't work nearly as well after DE is added. If you have a cartridge filter I would not add any DE unless your manufacturer specifically recommends it.

Using zeolite instead of sand can work well, but a noticeable percentage of zeo users have problems. Because of the potential for problems, I don't normally recommend using zeo instead of sand.

 

[zea3]

Thanks.

I'll have to locate a source for the FiberClear, and give it a shot. DW is all about green, and DD wants the water filtered better. Unfortunately, neither of my local pool stores have ever heard of it. I guess I'll have to find an online source.

Tim.

It is available from Leslies online and in stores.

 

[PoolGuyNJ]

Since you have a sand filter, add some clarifier. The thick blue gooey stuff causes anything the sand misses alone and allows it to be captured or fall to the bottom to be vaccumed. If there is visible stuff at night, 4-8 oz. per 10k gallons will clear it in a few days.

DE in sand filters is going to muck the sand up. I only do that as a last resort. It rarely fully backwashes out and leaves the filter with a smaller surface for filtering. Often, removal of the MPV and scooping the top inch or two and refilling with a fresh bag of pool sand solves that.

Scott

 

[JasonLion]

Clarifier is usually a waste of money. In some specific situations it can help dramatically, but most of the time it does nothing.

DE in a sand filter works quite well. I have been doing it for years with great success. Many many other people on the forum have also used it. The great majority of them had positive results, and none had any problems.

 

[baudilus]

I went into my local pool store to check out prices - a 24lb box of DE (4 x 6lb bags) is $19.99.

They also had one of these cellulose fiber DE replacement bags (but not Zeo Fiber) for $14.99. I bought that and now have it in my garage, ready for the new season. I figured a) I didn't want to have a box full of a carcinogen in my garage since I'd only be using a few cups at a time and b) it's biodegradable, so backwashing it out to the forest behind my house would certainly do less harm to me and my environment.

The bag says that 3 pounds replaces 25 pounds of DE, and it also suggests using it as a supplement for sand filters right on the bag. Funny, because the guy in the store was like "Why do you need DE if you have a sand filter? Give me about 3 or 4 months and I'll tell you how it does!