DE filter requiring constant backwashing

[BassPlayingDude]

Do you have a multiport valve? If so, you could set to recirc .. keep slamming until all the algae is dead, turn off your pump for a bit to let things settle, and vacuum very thoroughly out to waste before bringing your filter back into the loop. I do this to clean up my pool when I open every spring just to avoid having to tend my DE filter so much... YMMV.

 

[bjohannes]

I’m curious, what are you using as a “scoop” for DE? Is it a DE scoop like the one pictured here (each scoop is 1# of DE)?
View attachment 342927

If so, you are adding way too much DE to your 4820 filter. Per the Hayward manual the proper amount for the 4820 filter is 6# (6 scoops).

I'm using this blue scoop, which states 1 scoop per 5sqft of filter area. I always thought the Hayward manual was saying 6 actual pounds of DE by weight.

 

[Jimrahbe]

B,

Be careful with what is called a "scoop".. There are a ton of different ones out there.. Only a few of them actually hold a pound of DE..

I suggest that you test the one you have to see how much DE it actually holds.

Thanks,

Jim R.

 

[bjohannes]

B,

Be careful with what is called a "scoop".. There are a ton of different ones out there.. Only a few of them actually hold a pound of DE..

I suggest that you test the one you have to see how much DE it actually holds.

Thanks,

Jim R.

This one holds about 360g, so if Hayward's "recommended amount of D.E." of 6lbs by actual weight, it'd be about 7.5 scoops.

 

[zea3]

When you have the scoop designed for DE, 1 scoop = 1lb. You should use 6 scoops. They actually measure by volume and not weight, which is really confusing for most folks.

 

[BassPlayingDude]

B,

Be careful with what is called a "scoop".. There are a ton of different ones out there.. Only a few of them actually hold a pound of DE..

I suggest that you test the one you have to see how much DE it actually holds.

Thanks,

Jim R.

Be aware that there are two different amounts of DE, one if the filter is totally empty after you have deep cleaned it, and the other is after backwashing. The after-backwash amount is about 75% of what you would use if the filter was totally empty of DE after a deep clean.

 

[anthonypool89]

Do you have a lot of stuff that falls/blows into the pool? I

Yeah...you could say that. Unfortunately part of what is coming off the fields is probably stuff that is not readily apparent. They'll be cutting the field right next to the pool any day now. After they did that last year is when all (you-know-what) broke loose. All the fields near us are now in need of cutting, so I have no idea what to expect. On a totally unrelated subject...poison ivy seems to be particularly bad this season. I was doing some work on the woods paths that I maintain (except they're on property I don't even own...long complicated story) and cleared away a downed tree that was covered in poison ivy vines. I usually don't get it too bad, but this time have a really bad case of it on my one arm.

what are you using as a “scoop” for DE

I use what is in the picture - 6 scoops everytime I recharge the filter.

 

[Saturn94]

When you have the scoop designed for DE, 1 scoop = 1lb. You should use 6 scoops. They actually measure by volume and not weight, which is really confusing for most folks.

This.

I suspect the OP is overloading their filter with DE.

I’ve been using the ”1# DE scoop” for my Hayward 6020 filter for 17 years without issue. Hayward says 7.5# for my filter, so I add 7.5 scoops to a completely clean filter.

I never have to backwash during the season. At closing I take it apart and give it a thorough cleaning. At opening in the spring it’s ready for me to add DE.

 

[BassPlayingDude]

@bjohannes Do you know what your baseline clean filter pressure is? This is what your system should return to after you backwash and replace DE. I have a single speed 1.25 HP pump and a 36 s.f. DE filter, and my baseline pressure is 18psi. I suggest checking in 10-15 minutes. If your pressure goes above your baseline right away, you are probably adding too much DE. ​

​

Another thing that can help is a product like the Slime Bag, a microfiltration bag that attaches to your return via a special fitting and can simply be rinsed clean with a hose. If you have a multiport valve, you could run on recirc for a while with one of these just to catch all the big stuff. If you don't have a multiport valve, you probably should. ​

 

[bjohannes]

This.

I suspect the OP is overloading their filter with DE.

I’ve been using the ”1# DE scoop” for my Hayward 6020 filter for 17 years without issue. Hayward says 7.5# for my filter, so I add 7.5 scoops to a completely clean filter.

I never have to backwash during the season. At closing I take it apart and give it a thorough cleaning. At opening in the spring it’s ready for me to add DE.

Crud. This would mean I've been adding about 60% more DE than required. Not sure why the scoop says 1 scoop per 5sqft of area. I'll try with 6 scoops and report back!

 

[bjohannes]

@bjohannes Do you know what your baseline clean filter pressure is? This is what your system should return to after you backwash and replace DE. I have a single speed 1.25 HP pump and a 36 s.f. DE filter, and my baseline pressure is 18psi. I suggest checking in 10-15 minutes. If your pressure goes above your baseline right away, you are probably adding too much DE. ​

​

Another thing that can help is a product like the Slime Bag, a microfiltration bag that attaches to your return via a special fitting and can simply be rinsed clean with a hose. If you have a multiport valve, you could run on recirc for a while with one of these just to catch all the big stuff. If you don't have a multiport valve, you probably should. ​

I think baseline is about 8psi for me (equipment pad is about 6' above water level). I'll check out the slime bag, thanks! Sounds like the same idea as a skimmer sock.

 

[cj133]

I think baseline is about 8psi for me (equipment pad is about 6' above water level). I'll check out the slime bag, thanks! Sounds like the same idea as a skimmer sock.

I like the idea of the slime bag more.
It's always better to put the load on the outlet of the pump rather than the inlet.

 

[phonedave]

I think baseline is about 8psi for me (equipment pad is about 6' above water level). I'll check out the slime bag, thanks! Sounds like the same idea as a skimmer sock.

Skimmer socks are before the filter, the slime bag is after. So you would think that the slime bag is not going to help - its not helping to keep the filter clean.

Well, I think differently, based on a grand total of observing one person - me.

I used to have to clean and recharge my DE filter once a season due to pressure rise (about after 2 months). I would also get a fine 'dust' on my pool floor occasionally. I would have said dead algae except for the fact that my FC stays steady, my CC are zero, and I pass an OCLT. I gave up trying to figure out what it is. However, I would have to vacuum multiple times before I could get rid of it. Then I started using a slime bag whenever it appeared. It took care of it with one cleaning. Then I noticed that my filter pressures started staying low all season.

My theory is that whatever is in my pool is really fine, and after a while it does finally get stopped by my DE filter, but it really plugs it up. The slime bag (which is a much finer filter than a skimmer sock) grabs that stuff before it can build up in my filter.

That is my theory for now.

 

[BassPlayingDude]

Skimmer socks are before the filter, the slime bag is after. So you would think that the slime bag is not going to help - its not helping to keep the filter clean.

Well, I think differently, based on a grand total of observing one person - me.

I used to have to clean and recharge my DE filter once a season due to pressure rise (about after 2 months). I would also get a fine 'dust' on my pool floor occasionally. I would have said dead algae except for the fact that my FC stays steady, my CC are zero, and I pass an OCLT. I gave up trying to figure out what it is. However, I would have to vacuum multiple times before I could get rid of it. Then I started using a slime bag whenever it appeared. It took care of it with one cleaning. Then I noticed that my filter pressures started staying low all season.

My theory is that whatever is in my pool is really fine, and after a while it does finally get stopped by my DE filter, but it really plugs it up. The slime bag (which is a much finer filter than a skimmer sock) grabs that stuff before it can build up in my filter.

That is my theory for now.

I was recommending slime-bagging on RECIRC to bypass the filter completely until a lot of the heavy gunk was removed.

 

[bjohannes]

I like the idea of the slime bag more.
It's always better to put the load on the outlet of the pump rather than the inlet.

I’m curious, what are you using as a “scoop” for DE? Is it a DE scoop like the one pictured here (each scoop is 1# of DE)?
View attachment 342927

If so, you are adding way too much DE to your 4820 filter. Per the Hayward manual the proper amount for the 4820 filter is 6# (6 scoops).

Any idea what the actual volume of this orange scoop is? My "Blue Devil" 1lb scoop holds about 1 liter of water.

Interestingly, I just talked to Hayward's support line, and they told me the 6lbs in the manual was actual weight of DE, and not volume. They didn't seem to know anything about DE scoops though, so I'm not confident in their answer.

 

[zea3]

Support line folks are just reading out of the manual, they generally don't have any specialized training.

 

[Saturn94]

Any idea what the actual volume of this orange scoop is? My "Blue Devil" 1lb scoop holds about 1 liter of water.

Interestingly, I just talked to Hayward's support line, and they told me the 6lbs in the manual was actual weight of DE, and not volume. They didn't seem to know anything about DE scoops though, so I'm not confident in their answer.

Tomorrow I’ll try to remember to see how much water my orange DE scoop holds.

 

[Saturn94]

To make matters more confusing….

How Much DE to Add? - INYOPools.com - DIY Resources

The article will tell you how much DE to add to your pool filter and show you the easiest ways to measure DE powder.

www.inyopools.com

Hmmmm….. our orange scoop was provided by our pool builder and it included a conversation chart for measuring other dry chems with the same scoop. The chart says 1 scoop DE = 1#, 1 scoop CYA = 3#, etc. I know when I measure CYA with it, it comes out right.

BTW, I’ve never actually weighed a full scoop of DE.



PS - I found a pic of the conversation chart

 

[bjohannes]

To make matters more confusing….

How Much DE to Add? - INYOPools.com - DIY Resources

The article will tell you how much DE to add to your pool filter and show you the easiest ways to measure DE powder.

www.inyopools.com

Hmmmm….. our orange scoop was provided by our pool builder and it included a conversation chart for measuring other dry chems with the same scoop. The chart says 1 scoop DE = 1#, 1 scoop CYA = 3#, etc. I know when I measure CYA with it, it comes out right.



PS - I found a pic of the conversation chart
View attachment 343271

 

[zea3]

Originally, one scoop of DE was measured using a 1 lb coffee can. DE scoops were developed that held the same amount of DE as a 1 pound can. Then the 1lb coffee can became history, the only size close is 10-12 ounces.