Water Pressure

lcolon · #1 12/02/2001, 06:37 PM

I installed a Kent Marine Hi-S Maxxima 60gpd RO/DI
about 6 months ago when I first set my 90 gal tank. I've always had lousy water pressure and the gauge used to indicate 40psi but lately it's down to less than 20psi.

I took out the first two filters and rinsed them off and the pressure went back up for a while. Would changing the filters help improve the ro/waste ratio. Is a 1 micron filter better than 5m or 10m? I purchased a 10m filter at The Home Depot. I rather not buy a pump if I don't have to.

Skipper · #2 12/02/2001, 11:29 PM

Hey lcolon. I don't have the answer, but I will copy this to the Reef Discussion forum. Maybe someone there will know.

Skipper · #3 12/03/2001, 05:33 PM

[top]

JerseyReef · #4 12/03/2001, 06:11 PM

When was the last time you changed your pre-filters? If it's been longer than 4 months you should replace them. I f you really want ot know which filter is clogged, do this (it's simple)...

First remove the sediment filter, run the RO/DI. If the pressure doesn't go up, remove the carbon filter next and run the RO/DI again. If the pressure went up then your last filter (carbon) was clogged.

Now if your pressure still didn't go up then your RO filter could be clogged. This is a little more difficult to troubleshoot. You'll need to measure the rejection rate of the RO membrane.

Try the pre-filters first, if it doesn't fix it I'll go over the RO rejection with you (some math involved).

HTH

Jeff Hood · #5 12/03/2001, 08:32 PM

My spetrapure came with 0.5 micron prefilter and 0.5 micron Carbon block filter. The smaller micron size is preferable to keep your R/O membrand from cloging up. The instructions that came with my unit states that when the pressure drops 15 to 20% or every 6 months which ever comes first you should change the prefilter and carbon chambers. I would think the larger micron filters will work but will let larger particles through and possibly clog your expensive membrain. Also if you don't change your carbon block and you get clorine through to your membrain it could damage it.

Change your prefilters with as small of a micron rating as you can.

Your R/o unit is suposed to have 60 psi to deliver its rated flow. My water pressure here is even worse than yours. Its only 35 psi. To figure what flow you should be getting a rough guide is to divide your actual water pressure by 60 and multiply by your rated flow.

Actual flow = Actual water pressure/60 X units rated flow.

Temp actually affects flow but unless your water is very cold doesent matter that much.

Jeff