How much DE to add!

[Remark37]

Hi,

I know this has been talked about a lot and after researching different threads, I'm still confused!

I have a Hayward EC65a. The filter says to add 6 lbs of de and has a filtration area of 26.9 ft2. I have an Aladdin 300 scoop, as the picture shows. The scoop says to add one scoop per 7.5 ft2 of filtration area.

One scoop, I weighed to be 11.2 oz not including the scoop itself. If I go by the filtration area, I should be adding 3.59 scoops of de, 26.9/7.5. If I go by weight, I should be adding 8.57 scoops of de, 6 lbs * 16 = 96 oz/11.2 oz = 8.57.

I feel I should go by the manufacturer, which would be the weight or 8.57 scoops. Or maybe I am missing something obvious and overthinking it. But I assume there are a lot of other people confused and I hope the way I presented it helps not only me but others. I also understand that there is some pretty crazy math that goes with this and is over my head!

Thanks everyone, this is a great site and really helps a lot of people out!

 

[bob22]

I go by the weight; I don't think "scoopfuls" is a standardized volume.

 

[YippeeSkippy]

Got an old cheap diet scale? That's what I use to measure my dry chemicals.

 

[Remark37]

I go by the weight; I don't think "scoopfuls" is a standardized volume.

According to Aladdin and many de instructions, “scoopful” is standard, hence why it is in their directions.

 

[Remark37]

Got an old cheap diet scale? That's what I use to measure my dry chemicals.

Thanks! That’s actually what I am using. I suppose my confusion is how can they be so different? Almost 5 scoops different! I will go with the manufacturer but I assume many people go off of the scoop or de box.

 

[jark87]

My scoop is supposed to be a 1 lb scoop and has a mark at the halfway point for 1/2 pound measurement. I’ve never weighed the DE. My filter requires 7.5 lbs, so I put in 7.5 scoops and it has worked for 14 years.

 

[Remark37]

My scoop is supposed to be a 1 lb scoop and has a mark at the halfway point for 1/2 pound measurement. I’ve never weighed the DE. My filter requires 7.5 lbs, so I put in 7.5 scoops and it has worked for 14 years.

Thanks! It seems the morale of the story is to disregard the scoop instructions!

 

[Saturn94]

My scoop is supposed to be a 1 lb scoop and has a mark at the halfway point for 1/2 pound measurement. I’ve never weighed the DE. My filter requires 7.5 lbs, so I put in 7.5 scoops and it has worked for 14 years.

I have the same filter, and like you, I’ve always used 7.5 DE scoops. It’s been working fine since 2004.