At what ppm levels should i invest in a RO system?

My tap water is ~7.1 to 7.4 PH and ppm is 190. Tried searching the forums for a general concensus of what is a high ppm number that warrants purchasing a RO system, but not finding a key number. Does anyone have any wisdom they can bring to the table or could advise me if i should invest in the RO unit. Is 190 a high ppm?

Man my water ph is 6.9 and PPM is 217 from the TAP!!
I've heard from many experts here the TAP WATER IS TOTALLY FINE FOR hydroponic
Just for flush you should use something like Clearex from botinacare or other brand

If you are not having any problems you should think about otherwise just save your money hard times are coming brah!!

your tap water is just fine, actually much better than other places

most should tell you that anything over 200ppm you would want an ro system, but what a pain in the ass. my tap is 120ppm at 7.1. i see more problems from people running aero and ro.

thanks to all that replied. such a relief. i did not want to drop a few hundred on a water filtration system.

depends on what's in it, if your water company uses chloramine , def a chlorine filter. I've read 200 to be tops on ppm acceptable for hydro

and on personal experience I ran hydro for a year and a half or better and the PPM stayed at a consistent 70. Then what seemed like overnight it quadrupled to 280 and I started looking for threads here that were in the local area and found one started by a dude I can't remember his username who went on and on about chloramine killing in hydro, so anyway after my tap ppm quadrupled things started dying left and right in hydro for me, enough for me to switch to soil since I couldn't afford a RO filter at the time, been in soil since, coming out as we speak. If I fail now I know it wasn't the shit in the water.

Hey dbkick, how do you know if the water company is using chloramine? I've had nothing but problems using tap with hydro and my ppm is 190, ph 8 out of the tap. It took my some very miserable lessons to figure out it was the tap. But I think it was do to low mg, so I'm going to add some CaMg as soon as I can figure out how to feed it. The chart says 1 tsp per gallon, so is that per gallon of res?? So if it's a 20 gal res, add 20 tsp? I know the tap should not need mg, but I think it is do to low Ca and it locked out the mg, that's why I'm going to add it. Plus the crop definitely looks like a Mg deficiency.

You should also consider that the ppm levels and the particles that comprise the levels will not be static from week to week or even day to day.

Best to strip it all for a controlled environment.

I would also like to know the answer to his question if anyone knows

Rickety Rocket said:

I would also like to know the answer to his question if anyone knows

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the regular tap water chlorine is okay for the plants, you need a silly amount of chlorine to hurt your plants. if you are still worried, you can simply get a backup res, fill it up leave it open for 2 days, chlorine will evaporate, but hey, I like the low dose of it, because it keeps things cleaner

under 200 should be fine... mine is 600+ from the well and my RO takes it to 0-10ppm... for 60 bucks and 2 years strong on same cartridges best money I ever spent.

Don't buy one if you have that good of water from the tap, you will be fine.

Yeah, if your ppm is below 200 there should be no problem mixing it with a run of the mill grow/micro (lucas) formula. GH considers water to be hard after 200 ppm so you should be fine. Not that you can't strip it down to near 0 ppm and reconstitute to your desired hardness (most fertilizers work well with some existing Cal/Mag hardness from the tap, in fact the fert companies that make grow/micro formulas suitable for lucas ratio formulate with that in mind), but it would just be a wasted effort and you might end up a little deficient in calcium (small chance but it has happened to me, I write from experience) if you don't make-up the lost beneficial hardness with a little bit more cal/mag.

BigBuddahCheese said:

under 200 should be fine... mine is 600+ from the well and my RO takes it to 0-10ppm... for 60 bucks and 2 years strong on same cartridges best money I ever spent.

Don't buy one if you have that good of water from the tap, you will be fine.

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Which one you got Big? Been trying to find a good one for days now, finally got the flow I need to buy the damn thing. It's a pain the ass to have to buy a gallon a day of water, the time and the money wasted is ridiculous. I'm going to try more streamline approach, starting with the R/O filter. Any info would be helpful bro.

AWnox said:

Which one you got Big? Been trying to find a good one for days now, finally got the flow I need to buy the damn thing. It's a pain the ass to have to buy a gallon a day of water, the time and the money wasted is ridiculous. I'm going to try more streamline approach, starting with the R/O filter. Any info would be helpful bro.

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I did alot of research and ended up getting mine from APEC at freedrinkingwater.com

They say the most important things to look for in a good RO system are:

1. the actual RO membrane (the "heart of the system") And the film-tec by Dow Chemical is supposed to be the best.

2. that its made in the USA. (much better quality than the cheaper foreign ones)

3. that it is certified by WQA

I got the 5 stage 90 gal/day for $340. It comes with 4 gal pressurized tank, sink faucet, extra pre-filters and a free TDS meter.

I tee'd mine into a blue food grade 55 barrel, that i equiped with a float valve shut-off and a garden hose spigot. Works great. I always have about 45-50 gal of RO water
on hand. The filmtec filter is expensive to replace, but will last 5-7 years, if the cheaper pre-filters are changed every year.

I've ran several hundred gallons through it, and the TDS still reads.....001

The only bad thing with an RO system...is that it wastes alot of water. For every gallon of RO water you produce....about three gallons gets wasted. Unless you capture it and figure out a way to use it.

I put mine in my garage and use the sink faucet to fill a container that we use for drinking water(that water comes out of the 4 gallon pressure tank), and use the water in the 55 gal barrel for my plants.

I ended up extending the drain line tubing, and running it down the washing machine drain, so I wouldn't have to keep emptying buckets of waste water.

Rickety Rocket said:

My tap water is ~7.1 to 7.4 PH and ppm is 190. Tried searching the forums for a general concensus of what is a high ppm number that warrants purchasing a RO system, but not finding a key number. Does anyone have any wisdom they can bring to the table or could advise me if i should invest in the RO unit. Is 190 a high ppm?

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400 PPM is the cut off for safe drinking water in most areas.. so IF its ok to drink.. its ok for plants.. PS pure 6ppm 7 PH water is only 70c per gal at the store. I always have a few on hand.. for flushing.. if i think tap water is not cutting it

If you live any any sort of populated area that has a water source, you have access to the analysis of such water being provided to you publicly! Do your research! It is there for you!

My tap water is ~200ppm and I run it after letting it sit for several days. I have zero issues, and rarely change my reservoir because I can keep everything in check properly and don't have the need to actually do a change out.

PPM does not take into account the particulate matter in the water. Some places have good plumbing and others do not. The water quality report you can obtain from your public water supply is good for the water sample they tested and not much else. One more thing to keep in mind is that if your tap water is at 150ppm, then you have to ask 150ppm of what??

A quality (read, NOT ebay garbage) RO unit is a good investment (at least, it was for me.) A high quality Dow Filmtec membrane costs more than the Chinese made membranes include in ebay garbage RO systems. High quality carbon filters cost more than the shitty ebay systems, etc... You get the picture. Did I mention the ebay systems are garbage??

Things to look for in a quality system:

High quality RO membrane with a 98% or greater rejection rate. Auto shut off valve (you may not need this, but once you have one, you will understand how useful it is.) Pressure gauge, two stage particulate filtration.


Here is what you will shoot for: First particulate filter to protect the system....1 micron is fine but if you have lots of sediment in your plumbing, it will clog quickly. Second, is a 0.2 micron particulate filter. You want it this low, because you will want to protect your carbon block from being clogged. Third is a good carbon filter; 0.6 micron "chlorine guzzler" types are excellent. Your carbon filter is protecting your RO membrane so you want it to never ever not work. Fourth is a high rejection rate RO membrane. 90% is low quality, the good ones are rated above 95%. Chlorine kills RO membranes, so your carbon block must never clog. Your carbon block will never clog if your particulate filtration is rated at a higher filtration rate than the carbon. A 0.2 micron sediment filter will clog VERY quickly, so its a good idea to run a higher micron filter in front of it; 1 micron or 5 micron filters are quite inexpensive. I change them out the most as they tend to clog the easiest.

My RO membrane is going on 6 years old; it's a 150gpd unit and still offers a 99% rejection rate. The filtration system has a booster pump (good idea if you intend on making more than 15 gallons at once.)

There you have it, RO filtration forwards and backwards. I use the rejection water to fill my washing machine. Aside from the water having 25% more TDS than tap water, it's been filtered to 0.2 microns and has no chlorine. I'm not dumping that stuff down the drain!!

The 'ebay junk' 4 stage RO that I bought off ebay was 60 dollars with free shipping, I am getting 0 ppm water. Granted, its only a 50 gallon a day system, but its like the size of a 2 liter bottle and it was dirt cheap. It does have a auto shutoff valve, however, I just run it right into a 50 gallon tote, turn it on, and let it run overnight while I am sleeping. I only use 25 gallons at a time so by the time I am awake and ready to go change the res, my water is ready. When I am done, I just disconnect it and put it away. Once again, it weighs like 5 pounds and is the size of a 2 liter. It is rated to do 2500-3000 gallons, but that is at 0 ppm, it is actually good for many more gallons of 1ppm and 2ppm water.

You have to ask yourself. Is 60 dollars worth getting RO water on demand? Is it worth spending $3-400 on a system that does the same thing? 3-400 is a new tent, a new 1000w digital setup, a new AC, a new system, an entire co2 setup with controller, a new blue lab ph/ec/temp meter, ect. If you have all these things and extra money, it might be something to consider, but if you don't have a maxed out system the money is better spent somewhere else, besides, the hundreds of extra dollars don't buy you anything extra except bragging rights since the ebay ones do the same thing.

I bought my RO filter because I have fish, and I use it for them too. Also, I figured once I bought CO2, a new 15k btu ac, a giant dehumidifier, decent meters, and a 1000w air cooled light I didn't have anywhere else to go. My tap water is about 150-200ppm. I just wanted more control.

Alternatively, if you have a dehumidifier, you could easily just use the water from that. I get about 3-4 gallons a day from mine and I use it to water my mothers without ill effect. The water is generally at about 2-3 ppm. I set my big dehumidifier up on a table and took the drain plug out and just let it drip into a 5 gallon bucket or a tote depending on what I got going.

I use an aquasana filter type system under my kitchen sink. It's not RO but it's way better than a brita type filter. It does the job for me and the water is delicious to drink.