I have a DE filter and this will be the first year/attempt opening the pool by myself versus a pool service. I'm confused as to when you finally get around to starting the pool filter and priming it.

1) Do I have to backwash right away once the filter is primed (before adding any DE)? or
2) Do I add DE once the filter is primed and then vacuum and then backwash?
3) Do I have to backwash at all initially?

I feel as if I don't add DE almost immediately the filter is going to be coated with gunk/algae and then the coat of DE on top of that. One video I have watched online recommends you set your multiport valve to waste as to not get the gunk into the filter. If that's the case ...

1) Does the filter getting properly pressurized if the multiport valve is initially set to waste when I first turn it on the system?
2) After running on waste and then running on filter should I backwash and then add DE? or
3) After running on waste, should I then backwash, and then add DE?

Just to clarify, so I don't come off sounding completely hopeless, I do realize the point of backwashing is to flush the dirty DE out of the filter. I'm just wondering if there's a different procedure upon initial opening because the grids might initially get coated with gunk before you even get a chance to add DE.

Sorry if any of these questions come off as stupid. I just want to make sure not to damage any equipment as I do not have the money to make any major replacements/repairs. Thanks for any input/advice in advance.

Welcome!

Have you read this post: use-and-care-for-de-filters-t4086.html

What brand and model DE filter do you have? Do you have the owner's manual? If not, have you tried a GOOGLE search?

Hope this helps get you started. You are right in not wanting to cause any damage to your equipment.

Running to waste doesn't involve the filter at all.

As soon as you have the pump running and set to filter you should add DE. A couple of minutes after you add DE, note the filter pressure. That is your clean filter pressure. There is no need to backwash until the filter pressure goes up about 6 psi above the clean pressure.

I haven't read that post prior to you posting it, thank you for that information. I have a Hayward filter I believe. I need to confirm this in the morning and then maybe find a PDF of the manual.



Ok thanks. I'm thinking I'll initially set the port to waste for the initial system start-up of the season. I'll run it for a little bit to clear out the immediate gunk so it doesn't coat the filter. After that I'll switch the multiport to filter and the immediately add DE and then test the water. Do those seem to be logical and safe steps to get started?

Thanks for the quick responses, it's appreciated.

Do you know for sure that the filter is empty? It might be worth opening it up and manually cleaning the grids first so you know theyre completely clean and the start up and add the DE immediately. I've never tried but I think you could even add the de to the filter while it's open qfter you put the grids in it. Has anyone tried this?

I cleaned the grids last fall when closing the pool for the season. Why would you add DE to the filter while it's open? How is that even possible if your filter is open? I can see water going everywhere and not back out to the return if you were to do this.

The pump is not running and would have little or no water in it. You would mix up the DE in some water and pour it in the bottom of the filter body after the grids are put back in, then you close it up, set valve to filter and fire up the pump.

I actually asked the pool guy who services my neighbors pool today and he said he's added de into a filter like this when he was diagnosing a filter that wasn't cleaning, he popped it open and saw that there was not enough de, so he just dumped some in and closed it up etc.

I don't see why this wouldn't work - seems like one less thing to do and since you have the filter open anyway why not?

It's a viable way of adding DE to a filter - use the 'slurry method' It's especially helpful if teh pool isn't full enough to turn on the pump when you open.

There's the vote of confidence I was looking for.