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Reverse Osmosis questions

B00st3d

Member
So I have realized my water is why my plants arent up to par. I use a Tall Boy filter which takes out chlorine and sediment. However the water comes out at 160 ppm according to my milwaukee TDS pen and at 6.8 ph or so. So by the time I add the "lucas formula" and enough PH down to get to 6.0, my ppm's are over 1500 on my pen. Not to mention all that ph down isnt good, I know its leading to nute lockouts.

I also notice that my filter which is rated at 2 gallon per minute is only flowin at half gallon per minute accordin to my inline "flow meter" So is that filter holdin back water pressure or is half gallon per minute what my faucet in there is capable of maximum? Will an RO filter flow out alot slower? I notice they dont rate them in GPM instead they go by gallons per day and they are all rated very very slow compared to what I have now. Even a 600 dollar RO filter seems like it will flow slower then what I have now.

The flip side is that RO water will come out at a lower PH meanin very little PH down will be needed. Right now I have to add over 3 teaspoons per gallon of PH down to get my lucas formula'd water down to 6.0!!! Thats insane. That 3 teaspoons adds several hundred PPM's which is just empty PPM's to me that do nothing but cause other nutes to lockout. Even a gallon of plain water with no nutes , once I PH it to 6.0 , comes out to over 650 PPM on my Milwaukee pen. Im pretty sure thats unheard of and def not safe.

So what I want to do is get an RO filter in hopes that I will solve my hardwater issues and get a lower PH. My PH doesnt change once I add my GH nutes, it stays around 6.8 or so, so in theory when I add my nutes to the RO water it should also stay the same, right around 6.0, right ?

Which RO filter is everyone else using and whats the most bang for the buck? I know I will prolly have to spend 600 bux. I need to be able to produce 8-12 gallons of water per day and like I said, I want it to be around 6 ph and have little to no TDS at all. I wanna fill two 5 gallon jugs at once, add my nutes and PH if needed. I dont want it to take me an hour or two either cuz hand watering all these 5 gallon buckets is a pain in the ass as it is. Am I on the right path here, does this all make sense? Im thinkin it does and I think this is the solution to the problems Im havin now with yellowing plants, smaller top colas then I should have and havin to buy a ton of PH down.
 
I do passive hydro so aim for a pH of 6.2. With ro water and the lucas formula I need pH up, I'd be puzzled if that weren't true for every other lucas/ro user.

As it happens, Liquid Silicon can be used as pH up and it's stuff some people give to plants as an additive anyway. Supposed to help prevent mould and it sure seems that way in my grow.

To keep life easy, the ro line goes to a float valve in my ro res bucket (which sits on a table,) so always the same volume. I squirt in the same amounts of micro, bloom and LS as always then pour it into a bucket on the floor. Job done, haven't needed to use my meters in almost a year.

Forgot to add:

Medium hard water in my area and a 3 stage unit does the job just fine. A 4 stage at most would probably do fine for you, they're weeds not delicate tropical fish. If you use a float valve, have a check off valve as well or the waste will be running 24/7.

Room temps make a difference to output. Mine is in a cold cellar, 100 gph membrane and it takes about 4 hours to get 5 gallons. You could have a large ro res with float valve and take from that as you need it.
 

B00st3d

Member
so what ph does your RO water come out to b4 u add anything? Im wasnt plannin on using a res .I was gonna start using two 5 gallon jugs. Sounds like Im gonna need to do something like youre doin tho as slow as its gonna be, I cant be standin there waitin for water to come out. I didnt know the air temp made a difference. I know nothing bout RO systems obviously.
 

FreezerBoy

Was blind but now IC Puckbunny in Training
Veteran
Right now I have to add over 3 teaspoons per gallon of PH down to get my lucas formula'd water down to 6.0!!!

This is the part that throws me. Nutes are acidic, the more you add the more pH drops. My tap is pH 7.6 and Lucas at half strength nearly removes my need for pH down. Dropping your pH from 6.8 to 6.0 shouldn't take much more than 0.01 ml of pH down. That's about one single drop.
 

B00st3d

Member
well back when I didnt use any filter at all , my nutes would drop the PH but that was when I was using Fox farm nutes. Then all at once I switched to the tall boy , coco from FFOF and GH, this was in january of 08. Now I dont get much if any PH drop when I add the GH nutes. Im not even using full lucas. Im using 10ml bloom , 5ml micro and sometimes 1.25 or 2.5 ml of calmag with the occasional floranectar and liquid karma. Im tryin to cut back alot and just use one or two things along with the RO water and make everthing as close to perfect and functional as I can. I waste far too much time standin there fillin empty deer park gallon containers, addin nutes and then ph down.
 
Yeah a float valve makes life a lot easier, well worth the price of it plus the check valve.

For your tap water I'd suggest hydro shop pH down or maybe sulphuric acid from the motor parts shop.

Long long time since I measured unadajusted nutes in ro, about 4.3 iirc.
 
S

sparkjumper

Google the RO45 by Apec.Its what I use and many others I know.A great 5 stage unit for the money.You will see the difference.Flowering plants that used to stand straight and tall will suddenly be bending over like drunken sailors from the weight of the buds
 

B00st3d

Member
looks like a nice unit but seems a bit slow to me. Only has a 45 GPD membrane, I was thinkin more like 100-150 GPD membrane. Am I gonna get better quality with a slower membrane ? The Reefkeeper with 200 GPD is only 390, what makes the RO45 better. Explain please since Im so new to this.
 

B00st3d

Member
thats great Razor ridge but that doesnt help me at all. I wanna buy an RO system in the next few days and cant make up my mind what I want. I still like the reefkeeper for bang for buck.
 

B00st3d

Member
So should I bother buying one of those 10 or 14 gallon gallon storage containers that plumb directly into these systems? They run bout a hundred bux but seem very convenient
 
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sparkjumper

BOOst I had 25 plants in flower and maybe 30 in veg at all times and have plenty of water with my RO45.What I do is clamp on 1/2 inch plastic tubing to the R/O spigot and run it to a 50 gallon rainbarrel.I leave the spigot on and it takes around 18 hours to get 50 gal.I've never been short of water but if you're going a lot bigger than 50-60 plants go for the 90
 

B00st3d

Member
Thats a very good idea. Which rain barrel do you use? They are very expensive. I found one called the Rain Wizard for a hundred bux but it has a brass spigot and Im not so sure bout my water running throu brass. I know for a fact copper is bad news but not sure bout brass. The ones I found that dont use brass are 170 bux and up. Also would I be keepin air diffusers or air stones in there to keep the water oxygenated? I know that raises the PH . I found one RO called The Waterfall and its 300 gpd 6 stage I think and its 550 bux, does not use a DI filter either. Whats the significance of using a DI filter whith my RO. Thanks for all the insight so far, its def helpin to steer me in the right direction.
 
S

sparkjumper

The rainbarrel has suited my greatly except those few times when I forgot to close the spigot and came home to a very wet kitchen floor lol.I've done several grows and still read 20PPM from a 350-400PPM water source.It makes a world of difference.I had a lot of calcium in my water which was apparent in my dogs water bowl.Too much calcium locks out magnesium period among other shittin problems.I'd say my RO unit was my second best decision behind co2 and a controller in the flower room.Water makes a major difference
 
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