Spin Off: RO Systems

[SundayGardener]

I would love to stop buying a grocery cart full of water just for the orchids every week. (I'm not the only one in town who dedicates a full cart to water, but after talking to others at the watering hole, I'm pretty sure I'm the only one getting water for plants).

I can get the 3-stage HydroStealth systems and filters locally. Home Depot carries APEC under-counter 5-stage systems which seem to be popular, but I don't know how this works for amassing gallons of water at a time. I need 18-20 gallons for a whole-collection watering. Aquarium supply stores have 5-stage systems that you can set up in your basement. They produce 0 TDS water, which is overkill for orchids--but would it be a problem for orchids, as long as I use products like K Lite?

I'm not sure that a 3-stage HydroStealth is the best solution for my water (municipal, chlorinated, hard). Asking the experts! My ideal system would be low maintenance and reliable. I try to support local store owners, and they said they would ship in a system other than HydroStealth if I wanted (buying online is cheaper, though ...)

[Ray]

I hope this doesn't offend you, but let me start with describing just what those "stages" are in a standard residential system, and how the others vary from that:

Stage 1 is a sediment filter to trap any suspended solids carried in the water.

Stage 2 is a carbon filter to trap chlorine and organic compounds.

Stage 3 is a second carbon filter, doubling its capacity to trap stuff. (Without it, the system is a 4-stage.)

Stage 4 is the membrane to reject the dissolved solids.

Stage 5 is a carbon polishing filter, to remove any last traces of organics.

A decent system also has a hydraulic cutoff valve in it that stops the input water flow when the storage vessel is full.

The Hydrologic 3-stage system is simply a residential 4-stage system (one carbon prefilter) that does not have the polishing filter.

Your aquarium supply shop probably replaces the polishing filter on a 5-stage system with a deionization cartridge to take the dissolved solids to near zero. You're correct, it is unnecessary for plants.

As your water is chlorinated, you should get a system that has two carbon cartridges before the membrane. Again, that would be a residential 5-stage system (or 4 without the polishing filter - be careful, that is not a standard setup, so be sure when purchasing - most "4-stage" systems have only one carbon prefilter).

Maintenance is simple: Replace the sediment filter every 6 months, the carbon prefilters once a year, and the membrane (and polishing filter, if you have one or keep it) every two years. (The components are actually rated as 3000-, 6000-, and 12,000 gallons, respectively, but the calendar scheduling is easier.)

Collection and distribution is the key. If you need 20 gallons per watering, I suggest you get a plastic 55-gallon drum (often free from local car washes), and put a small float valve in it. You can then set up the RO system to fill the drum through the valve. When you use the water, the float valve opens, the RO system refills it automatically, shutting off again when the tank is full.

You CAN get a large bladder tank instead, but they're pricey (about $200).

Yes, K-Lite, if used dilutely and regularly, will provide plenty of nutrients.

[SundayGardener]

Thanks, Ray!

I'm not offended at all. I tried asking my local store a lot of questions, and they couldn't really answer them, so I came here and you delivered!

[Ray]

If you have any more questions, we can chat on the phone...