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RO/DI Output Incredibly Slow


Daniel

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Hey guys,

I have a 75gpd RO/DI from Bulk Reef Supply that is unbearably slow. My water pressure is fine. I get maybe 5 gallons in 5 hours. Is this normal? Because I hope it's not. The membranes aren't very old, but they were equally slow when I first got them anyway.

Daniel

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What is the PSI on it?

What temp is he room where you fill it in?

What is the TDS reading for the water after it comes out?

How much waste water are you generating per gallon of good water?

Any signs of leaking?

Also the attachment shows a graph showing the effect of PSI and temp on the results on your unti. Also the other things I asked might help figure out what's going on.

0901b80380074538.pdf

Hey guys,

I have a 75gpd RO/DI from Bulk Reef Supply that is unbearably slow. My water pressure is fine. I get maybe 5 gallons in 5 hours. Is this normal? Because I hope it's not. The membranes aren't very old, but they were equally slow when I first got them anyway.

Daniel

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Hey guys,

I have a 75gpd RO/DI from Bulk Reef Supply that is unbearably slow. My water pressure is fine. I get maybe 5 gallons in 5 hours. Is this normal? Because I hope it's not. The membranes aren't very old, but they were equally slow when I first got them anyway.

Daniel

75gpd /24 hours = 3.125 g/h. You are getting more output than you are supposed to.

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Just noticed that it was 5g in 5 hours, not 1 hour. If you read several of the RO websites such as the FAQ on Buckeye, you'll see that several factors can cause your RO system to put out well below the stated amount. Things like water pressure, water temperature, and most importantly what your water is made up of can affect the output. I think I recall reading that if a filter is rated for 75g a day in perfect conditions that the average home can expect to see between 50-60g of water a day. I noticed a huge drop off of production when I move2d from Austin to Round Rock. When I lived in downtown Austin I was about 2 miles from the treatment plant right along the river. My pressure was near 110psi, the water was ultra clean to begin with, and soft. When I moved to Round Rock our initial TDS tripled, the PSI dropped to 80, and I noticed that the hard water and deposits severely impacted the production.

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Thanks for the feedback guys.

I'm not sure what the actual water pressure is, but it's plumbed to the cold water line on my kitchen sink. How do I figure out the actual water pressure?

I'm getting about 1 gph, which is less than the 3+ you guys mentioned. I don't see any kinks or leaks and the output isn't restricted. Should I be feeding warm water instead of plain cold water? The TDS reads 0 on the output side. Should I still try a new RO membrane? Maybe the one I have is just a little defective?

Which cartridges/filters do you guys use on the other canisters/stages?

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To determine the PSI many people use something like this http://www.google.com/products?hl=en&q...=1&ct=title . Check out the few product results towards the top. The PDF I linked on my first reply will show you a graph showing the relation between estimated gph of your filter at various pressure levels. But you have it plumbed to the right one (cold) but sometimes a person water pipe is too powerful or not powerful enough and that can effect your RO/DI unit.

Also you may want to try measure how much waste water you are getting per gallon of good water. Typically 3-5 gallons of waste water for every gallon of good water is fairly common for most people. If you are seeing ratios beyond that it could be that your membrane needs to be replaced but you might want to verify water pressure first if you can to rule that out (or confirm it as the culprit).

Thanks for the feedback guys.

I'm not sure what the actual water pressure is, but it's plumbed to the cold water line on my kitchen sink. How do I figure out the actual water pressure?

I'm getting about 1 gph, which is less than the 3+ you guys mentioned. I don't see any kinks or leaks and the output isn't restricted. Should I be feeding warm water instead of plain cold water? The TDS reads 0 on the output side. Should I still try a new RO membrane? Maybe the one I have is just a little defective?

Which cartridges/filters do you guys use on the other canisters/stages?

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