Can I add a cup or so of DE to recycled glass media?

[AUSpool]

I followed the other thread, AUSpool, and found my pool DE as a result, so thanks! I have my lifetime supply as well

I also used medium speed as my reference for the TFP instructions, and could see the gauge going up as I increased the DE. For me, it's 45 GPM (170 LPM) and 8 PSI rising to 8.75/8.9 ish. I run mostly on low speed around 32 GPM (120 LPM) and 4 PSI, so I thought the difference while adding the DE might be too small to see...

That's great, it's nice to put some numbers to it, my gauge is only green or red, not very technical. It used to have an audible alarm device that would go off when it went into the red but that was broken when I bought the house. I should revisit the idea of replacing it.

I mostly run on low too and at that speed I have no problem keeping up with my chlorine demand. And at 28c a kWh it costs around $70 a year to run. I switched to the glass when I put the Eco pump on as I had read that it had better flow dynamics than sand and applied less back pressure on the pump allowing for a slightly higher flow rate. If that is true in practice than the pore space would be slightly greater, the filter would tend to filter a bit deeper and potentially could let the very fine partical sizes through.

...
Plumbing is all 50 mm (~10% larger ID than American 2").

Na, it's all the same. I just installed solar heating using a combination of 40mm(1.5") and 50mm(2"). I bought all my elbows and tees in LA and the pipe from a local plumbers supply (Reece). 2" American fittings glue strait into Aussie 50mm pipe. The mm sizes are arbitrary and have no relation to ID or OD.

Good news! I love my DE!

Thanks Marian, I think it really does help.

 

[MarianParoo]

I have been using DE for several years and occasionally I neglect to re-add after a backwash... Usually I forget when it is pouring rain and I am trying to lower my water so I run back into the house. Anyway, I will lose a tad of sparkle in the water, then I panic thinking something's wrong, and then I remember that I never added new DE.

 

[needsajet]

Na, it's all the same. I just installed solar heating using a combination of 40mm(1.5") and 50mm(2"). I bought all my elbows and tees in LA and the pipe from a local plumbers supply (Reece). 2" American fittings glue strait into Aussie 50mm pipe. The mm sizes are arbitrary and have no relation to ID or OD.

Yeh mate I wasn't referring to OD, fitting or the nominal sizes. I was curious why my head loss calcs were coming out a bit better for Aus pipe, so I checked the IDs for pipes commonly used for pools over there vs. here. I just used the manufacturers websites for the ID info. Not important enough to worry about, but was one of those things I needed to understand in case my calcs were wrong! Metric gets my head spinning, cause I cut my teeth in feet of head loss and USGPM (and still prefer them!