good RO/DI unit

[nima]

does anyone know of a good RO/DI unit that doesnt cost a fortune yet does its job?

 

[raderman]

I have had great success with the Tap Water Purifier by Aquarium Pharmaceuticals. The unit is about 10% of what a RO/DI unit is and the replacement cartridge is like $17 dollars. IMO this unit is your best option when you compare the price and performance versus an RO/DI unit.
Especially, if your aquarium size is smaller than 75 gallons.

 

[adrian]

Check out what spectra pure has to offer. I have been using their 3 stage RO unit for 3 years now with no complaints. HTH