Account and Orders

Frequently Asked Questions

Water Temperature

Q: How does water temperature effect flow rates through RO filters?
A: Between 77° and 50° water system production declines by 50%, as cold water is more dense, more viscous, and more difficult to move through the membranes.

Q: What can be done to combat the effects of cold water on RO membranes?
A: Increasing the water pressure with a booster pump. Increasing the feed water temperature, which some people do by mixing warm and cold water from a diverter valve.

System Ratios

Q: Does the system ratio (waste ratio) change over time?
A: System ratios can change over time if the flow restrictor starts clogging due to hard feed water conditions.

Q: Does the system ratio change with water temperature?
A: System ratios (waste ratios) can drift with cold feed water. 
 Water travels the path of least resistance — the drain line! It’s important to check the system ratio during the winter months and adjust if necessary.

Q: How can the system ratio be adjusted?
A: System ratios can be tuned with a ball valve or Flow Box. Never go lower than the system was intended for.

Water Pressure

Q: How much water pressure is needed to run an RO system properly?
A: RO membranes require 40 psi of incoming pressure to produce even a drop of water except our GXM200-HF which requires only 20PSI.
 The only membrane on the planet that can do this.

Q: What’s the maximum feed water pressure that an RO system should run on?
A: Incoming feed water pressure on all water filters, always and everywhere, should be no more than 80psi. Plastic filter housings cannot handle more pressure.

Well Water

Q: Can all GrowoniX water filters be used with well water?
A: Well water is generally too dirty for small RO membranes (100GPD through 400GPD systems).
 The large 4” membranes of the bigger systems (600GPD and larger) are recommended for well water treatment,
 unless the water demand is really low.

Q: Are there any special filters needed to treat well water?
A: KDF85/ catalytic carbon filters are a must 
for well water treatment. This premium catalytic carbon filter with a bed of KDF85 media can reduce iron, hydrogen sulfide, heavy metals, and bacteria—all things that wreak havoc on RO components—especially membranes. Other consideration for special filters can only be deduced with a laboratory water analysis.

Q: Does GrowoniX help with well water analysis?
A: We do. Just send us your water analysis and we’ll look at it for free. If you don’t have a recent analysis, you can either use a local water lab, or purchase a test kit through GrowoniX send it off to our partner lab.


Water Analysis