Slow pressure increase when adding DE to sand filter

[Auburn02]

Followed this guide to add DE to my filter through the skimmer, which says typically plan to add 1-2 cups of DE. Read some other posts where people have only needed to add as little as 1/2 or 3/4 cup. I stopped at 4 cups today and while my filter pressure had moved, it still had not increased by the 1 psi target. Pump was running at 2750, if I recall correctly. Not sure if that means anything in particular, why on average people see the prescribed rise with as little as one cup and I was way over without seeing any.

So should I have kept going even if it meant adding 5 or 6 or more cups? Or should I have been doing this at full tilt on the pump?

 

[mknauss]

Adding DE is making the filter dirty. How much it takes to make it dirty is dependent on filter size, particulates in the water, etc.

Why are you adding DE to your sand filter?

 

[cowboycasey]

If your pool is not dirty and you have a big filter your PSI may not rise much.. You do need to continue to watch the PSI as it may rise fast if you have lots of debris..

 

[Auburn02]

Pool is not crazy dirty, and the filter is still new (6 or 7 months). Just completing my SLAM and trying to finish off collecting some finer bits I see primarily floating past the pool lights at night. I understand the point/effects of DE in a sand filter, just had not read of others who required so much of it to add that extra bit of filtering capability.

 

[cowboycasey]

I think you will be fine, just keep it where you are at and let the filter do its job..

Once you backwash it will all be gone..

 

[sktn77a]

Keep an eye on the pressure. It can go up quite a lot after an unpredictable amount of time, depending on how much algae you have in your pool.

 

[Auburn02]

The mystery continues. As I mentioned before I started at 10, added DE until it got to 10.5 and stopped there. About 24 hours later it was at 12, sweet, logical. Now another 24 hours later it's back to 10.5 or even less. Same pump RPM the whole time.

I'm not worried about it, just perplexed. I'll be leaving town for five days tomorrow so I'll backwash tonight regardless.

 

[cowboycasey]

if leaving do not add DE