View Full Version : Can you recommend me some products?

09/22/2009, 09:56 AM
I have a new client that is using their well water to supply RODI water for their 6 tanks. They have been having problems with unexplained deaths. I went through testing their water parameters and everything is checking out (except for low calcium and a pH that reaches 7.9 just before lights out). I then decided that I should check their supply water.

To my surprise their well water is testing at 800+ TDS. They have a basic 5 stage RODI that is not keeping up with the task. Their output after the DI hovers between 50 and 70 TDS. They are replacing sediment filters weekly as they are turning bright orange. They suspect the water to be hard.

Water pressure is also a bit low, hovering around 40-50psi.
What would you recommend for a system that is capable of handling such a high TDS, with hard water, and fairly low pressure?


09/22/2009, 06:28 PM
They would appear to have multiple problems one could be membrane but you didn't give me a RO reading after running 5 minutes. The second issue they have is low pressure which can be solved with one of our booster pumps. With the high TDS they need to get maximum performance from any membrane. 75 GPD Filmtec membranes are going to perform best with up to 98% rejection rate.

They may have another issue which is low pH supply water indicating high CO2. CO2 in high levels can rapidly exhaust DI and has no tds reading. Not uncommon with high CO2 to only get 50-60 gallons from a full sized DI cartridge before exhaustion. I guess I need some more details.


09/23/2009, 06:17 AM
I'll make sure to get you an RO reading and a pH reading. Anything else?