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Are RO Units Worth The Money And Effort?

jimscott

Tropical Fish Enthusiast
I can bring home purified water from work (WFI), but it's a hassle, with the paperwork and signatures and squirrelling away water. It would be nice to able to get water, 'on tap', as it were. Is RO water actually CP safe?
 
My RO unit produces water that has a TDS reading of 4 PPM. Been using that for 2 years now. Nuff said?
 
totally worth it.
 
if your talking about the same kind of unit i use its well worth the money as they don't cost much.Only drawback is mine produces about three times more waste (concentrate with high tds) than it does usable water.In the UK many houses are on a water meter and have to pay for that waste (i am lucky and am not)but i use the waste to water my ever thirsty tomato plants in the summer so all good
 
Probably worth it, but unless you're sure your water is full of minerals, check out tests posted online by your water supplier. I did that after 2 years of buying 10 gallons of distilled water pretty much weekly and found out that my tap water was literally almost pure water... TDS was super low. All my Sphagnum, Nepenthes, Sarracenia and Drosera are doing much better with the extra water.
 
It's my favorite CP purchase. I use it constantly. But I also have vivaria with misting systems I need to keep refilling.
 
It somewhat depends upon the quality of the local water. I was on a well and the ppm exceeded four hundred and change. I went through a membrane a year for a while; and the waste water produced by the production of the RO -- unless it is collected -- is intolerable under our current California drought conditions . . .
 
get a reading on your tap water. Mine works fine right out of the tap. But it is surface water. water shed filtered through ferns, mosses, etc vs aquifer.....
 
Folks have brought up a good point. My local municipal water supply comes in at 45ppm and would be perfectly good for cp use. However, I'm on a well and it is badly contaminated with iron, and straight out of the well it reads around 500ppm, so the RO unit was a necessity.

If in doubt, FIND OUT! ;-)
 
  • #10
As others have said, it completely depends on the quality of water at hand. My tap water originates from a very pure source near Mt. Hood and measures, on average, 18 ppm. I would go further to say that the minerals found within that small value are beneficial to the health of the plants. I feel more comfortable using this than I would distilled or RO water.
 
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  • #11
Alkalinity NR NE 91 61 - 97
Calcium Hardness NR NE 91 64 -107
Conductivity NR NE 301 uS/cm 200 - 346 uS/cm
Magnesium NR NE 8.6 8.3 - 8.8
Manganese NR NE 0.002 0.001 - 0.003
MIB and Geosmin NR NE ND ND - 2.7 ng/liter
Potassium NR NE 1.65 1.6 - 1.7
Sodium NR NE 14.1 13.9 - 14.3
Sulfate NR NE 21.3 21.0 - 21.5
Total Dissolved Solids NR NE 156 149-166
Total Organic Carbon NR NE 2.0 1.4 - 4.7
CRYPTOSPORIDIUM AND GIARDIA Number of Samples Tested
Number of Samples Testing Positive Violation
Yes/No
Sample Date
(or date of highest
detected)
UNREGULATED SUBSTANCES
Water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that the water poses a health risk.
Results presented here are from 2011 analyses or from the most recent year that tests were conducted in accordance with regulatory requirements. Some tests are not required to be performed on an annual basis. Information can be obtained upon request from the ECWA Water
Quality Laboratory (716) 685-8570 or on the Internet at www.ecwa.org .
AL = Action Level: the concentration of a contaminant which, when
exceeded, triggers treatment or other requirements which a water
system must follow.
CFU/100 ml = Colony Forming Units per 100 milliliters
MCL = Maximum Contaminant Level: The highest level of a
contaminant in drinking water. MCLs are set as close to MCLGs as
feasible
MCLG = Maximum Contaminant Level Goal: The level of a
contaminant in drinking water below which there is no known or
expected risk to health. MCLGs allow for a margin of safety
MFL = Million fibers/liter (Asbestos)
mg/liter = milligrams per liter (parts per million)
MRDL = Maximum Residual Disinfectant Level : The highest level of
a disinfectant allowed in drinking water. There is convincing evidence
that addition of a disinfectant is necessary for control of microbial
contaminants.
MRDLG = Maximum Residual Disinfectant Level Goal: The level of a
drinking water disinfectant below which there is no known or expected
risk to health. MRDLGs do not reflect the benefits of the use of
mrem/yr = millirems per year.
uS/cm = Microsiemens per centimeter (a unit of conductivity
measurement).
ND = Not Detected: absent or present at less than testing method
detection limit.
ng/liter = nanograms per liter = parts per trillion
NE = Not Established
NR = Not Regulated
NTU = Nephelometric Turbidity Units
pCi/liter = picocuries per liter
RAA = Running Annual Average
SU = Standard Units (pH measurement)
TT = Treatment Technique: a required process intended to reduce the
level of a contaminant in drinking water.
ug/liter (ug/L) = micrograms per liter (parts per billion)
Variances and Exemptions = State or EPA permission not to meet an MCL
or a treatment technique under certain conditions.
< = Less Than
< = Less Than or Equal To
 
  • #12
How much does an RO unit cost (approximately)?
 
  • #13
How much does an RO unit cost (approximately)?

It depends on the quality of the unit usually. I have a 75 GPD from Bulk Reef Supply, ran me about $200, and is of good quality. I've seen them down to around $100 at 75GPD but those are offbrand. More GPD is going to drive the price up as well. You'll find there are some extra features, such as built in TDS meters, with a lot of sellers that can alter the price as well.
 
  • #14
I have looked at units at Lowe's in the $100 - $175 range, though that was a few years ago. Don't know how good they are, didn't buy one.
 
  • #15
Looks like you could benefit from the RO for sure. ebay 100gpd ~$70. legit.
 
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  • #16
I would consult with Butch before purchasing a unit. There are many factors to consider - among them if the unit use "standard" filters and membranes that can be found readily. Some use odd size components and you have to buy them from one or two sources at inflated prices and get gouged on shipping.
 
  • #17
One consideration. All typical aquarium and home RO units use the same size membrane housing. The volume rating is a function of the interaction between the membrane and a flow restrictor located in the waste water line. When it's time to replace the membrane, you can easily upgrade a 10 gpd unit to a 200 gpd membrane and flow restrictor and convert a 10 gpd unit into a 200 gpd unit. The cost difference between the lower and higher output membrane isn't that much, a flow restrictor costs a buck or two.
 
  • #18
Question 1:
What water pressure do you have?

If less than 45-50 RO units perform poorly and require booster pumps.

Question 2:
Do you want this unit to supply water for other uses besides CP's?

e.g., personal consumption, humidifier, ice maker, etc

If yes, than you will want a captive air tank (accumulator) equipped system

Question 3:

Budget?

A "good" captive air tank and permeate pump equipped 100gpd system will run in the range of 200$.

Like most things, you get what you pay for. My system is 9 years old, supplies many gallons per day, every day and just now on the third membrane. Prefilter life is six months easily with a 3:1 Brine ratio.

Warren is correct about the non standard units. Some whirlpool and rebranded whirlpool units take unique prefilters and membranes. These result in a significant increase in routine maintenance expense.
(can be found at big box stores)

Here is a link to one, notice the prefilters are modular...

Caveat emptor
 
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  • #19
Just CP's. Thanks for the advice! I use ~2-3 gallons of water for the plants per week. Is it worth it?
 
  • #20
As a renter you need to find out if the landlord will allow you to make the necessary modifications to the plumbing for an under-the-counter installation. If not you need to look at faucet adapters for a "counter-top"/portable setup.
 
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