What do you guys do for water puriification?

[uryy4me]

I have been limping along on a Kent 35 gpd 4 stage ro/di and although the outpt has been sufficient I have been blowing through a lot of filters (especially when I forget to flush hte RO membrane before/after using it)....what is the most cost effective way to get about 300-400gpm of 0 tds water (city wateris at 250 ppm, comes out of the RO @ 14ppm and out of the DI @ 0 ppm)?

- scott -

[z28pwr]

I have a 5 stage 100 GPD RO/DI Unit from Aquatic Reef Systems. The setup runs $225 new. What this allows you is to use 100% of your DI cartridge by moving it down. If I have problems I may go to a 6th stage. Or buy another filter at home depot to put in front of the RO/DI so that the RO/DI unit get's a lower TDS water.


But looks like the 5 stage is good enough for now.

[Aged Salt]

Sounds good, I have a 4-stage, 65gpd but with a lg. system my TDS run 8 to 20. I'll add a 2nd micron filter/canister on the front end & hope that helps,Bob

[eruss]

I tooka 2-stage Spectrapure 24gpd unit and upgraded it to a 4-stage 100gpd unit with components from AQUAMAXX. Pretty simple to do and AQUAMAXX has good prices on pieces and parts. The web site isn't spectacular but hey.............. Working great for me so far but then my tap water is 79ppm to begin with.

As a side...I use refillable cartridges in my DI canister that I bulk-fill with mixed-bed resin from Resin Depot. A cubic-ft runs about $170.00 (including shipping) and will provide about 25-35 refills. I'm also considering putting a refillable cartridge before the DI with Poly-Filter discs in it to see if it stretches the mileage on the resin any appreciable amount.

[dgasmd]

I use a 100 GPD unit from ARS with a dual DI as well. I get about 65 gpd of 0 TDS with poor pressure. I am upgrading by adding another 100 gpd RO membrane and by putting in a pressure pump to increase the pressure. They tell me it should increase the output to about 280 gpd:eek1: :eek1: :eek1:

[Aged Salt]

eruss, that's a GREAT idea. Plz. post here your results,thnx. Bob

[eruss]

dgasmd - No doubt a booster pump will help with your output, especially if your line pressure is below 40psi now. Something else to consider is the temp of your feed water. Cold water (50-60 deg) will also reduce the output of the membrane. Can't take credit for the idea, but one way around this is to lengthen the feed tubing and coil about 25ft in a bucket filled with water and add an aquarium heater set at about 78deg. The slow feed rate of an RO allows the warmed water in the bucket to warm the feed water going to the membrane and...viola!...increased efficiency and output.

[acroporas]

Originally posted by eruss
dgasmd - Can't take credit for the idea, but one way around this is to lengthen the feed tubing and coil about 25ft in a bucket filled with water and add an aquarium heater set at about 78deg. The slow feed rate of an RO allows the warmed water in the bucket to warm the feed water going to the membrane and...viola!...increased efficiency and output.

Hey, why not do this in your sump - cheep chiller....

[dgasmd]

Thta is an awesome idea. I will give it a try. I have an even harder time during the winter making make up water and water for changes. It slows down to about half the output. I guess I can use my sump. That woulbe even easier.