Replacing sand with glass media - What is the correct replacement ratio? How high do you fill with glass?

Rockstead said:

I had to inspect my laterals and since I had emptied the filter I decided to just try glass media, it was just a few bucks more than sand.

The pool store said that you replace it 1:1 but the manufacturer (Bellemare) of the glass said it’s 42 pounds for every 50, so I replaced my 300 pounds of sand with 250 pounds of glass.

Typically is that a recommendation that should be followed, is there a better way to determine how much glass to put in to maximize my filter efficiency?

Thank you!

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The biggest issue is not weight but volume. You need to fill the tank to a certain height or it won't filter properly. The area above the sand/glass bed is the "freeboard." Your filter manufacturer may or may not publish that number. The filter manufacturer determined that 300# would be a proper fill for your filter. I would go with the glass manufacturer's instructions, they have determined the volume their bags will fill compared to the 50# sand bags. Sand is heavy, glass media less so.
If it doesn't work, add more. If you add too much, it will just backwash out until the proper level is reached, but the filter may not work well. Hopefully you have unions at the filter.

Filter model number?

Note: Freeboard is so important that Lynyrd Skynyrd made a song about it.

Rockstead said:

Hayward SM2506TP

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Use 10.5" for freeboard.

Rockstead said:

Thank you for the feedback.

My pump model is Hayward SM2506TP, I couldn’t find any documentation for where the freeboard level is, I don’t see it indicated on the filter either, I wish I had a visual cue to work with!

I’ll take your recommendation to stick with the glass manufacturer recommendations but I wish I could determine 100%

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If you worry about this, it will make you crazy.
The recommended amount of sand that is initially placed in a sand filter is based on the fact that you can usually only get sand in 50# and 100# bags. The actual amount needed in a "300#" filter may only be 295, 290, or ??
When you first load a sand filter and then backwash, as you should, before starting to filter, some of the sand that makes up that 300# will backwash out. It is the fine stuff that gets through the #20 screen when the sand is processed. Some of the glass-media instructions advised to do that, some said it wasn't necessary with their product. Don't know about yours.
Then, with each backwash a little more will be removed. For a 300# (24"/25") filter, after about 5 years with normal backwashes, you will have lost enough that a 50# bag of sand, if that was used, will usually be needed to restore the filter's efficiency. I never worked with glass media enough to determine if that was the case with it.

We do not recommend alternative medias for Sand Filters. There is no benefit to using it.

ajw22 said:

We do not recommend alternative medias for Sand Filters. There is no benefit to using it.

Sand Filter Use and Care - Further Reading

www.troublefreepool.com

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+1, but it was already purchased.

1poolman1 said:

+1, but it was already purchased.

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Can it be returned if unopened?

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