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urbanrunoff
05-05-2010, 07:40 AM
I'm still struggling with my pH, which hovers around 8.2.
It is not the grow media because my second system has hydroton as grow media and the pH is the same.
I talked to a guy who runs an AP system a couple of blocks from me and he had the same problems and he said it is our water and only when he got a RO system he was able to control the pH.

Here my question:
I see a lot of RO's(typical kitchen, under sink ro's) on craigslist, is it possible to modify these units and hook them up to a graden hose for outside use? Water pressure might be an issue...but i'm ok if it takes a couple of days to fill a reserve tank and then pump it into the FT.
I don't want to invest in a hydroponic RO system made for this if i can get a used one for under 100 bucks.

thanks

REEFBUG
05-05-2010, 08:41 AM
There is no problem in hooking an RO to a hose bib, a quick trip to the hardware store should get you the parts you need. Pressure should be the same as you have in the house. Just keep in mind the smaller ones are less than 100 gallons per day, so having a reservoir would be an important item.
Also as far as buying a used one, you will probably have to replace the filters and membrane, probably cost you about $50. You might be better off with a new on off ebay.

dufflight
05-05-2010, 05:20 PM
When you add acid to bring the ph down how long does it take to get back to the 8.2? If its not the media you may be able to work the buffer out of the water over time. I had high ph for a long time but it was due to media but the system has slowly worked its way through what ever was in it to buffer the ph. A little acid every now and then if I want to get closer to the 6.

badflash
05-05-2010, 08:02 PM
You need to figure out how much water you need per month to figure the true cost. RO is essentially pure H20. You can mix it 10:1 with tap and be in the zone. pH is a log scale so each point is the log of the next level, not just a multiple.

urbanrunoff
05-06-2010, 01:07 PM
reefbug: you might be right
dufflight: i started adding 5ml of HCL (100 gallon FT plus 25 gallon duckweed conatiner) every evening and looks like i keep it around 8 with that method (without it i'd say it goes to 8.2 and up)
by the way i put acid mixed with water in a cup with a hole and let it drip slowly into FT.


badflash: that's a good idea.

anyboy know if there is a easy de-ionizing filter that can be hooked up inline.... instead of the full r/o setup

anyways thx everybody.

dufflight
05-06-2010, 05:23 PM
Try and bring it slowly down, 6.5 is a good area and the plants will go nuts. 8 is pretty high.

badflash
05-06-2010, 08:12 PM
The system may bee too clean as well. Waste and left over organics will add acid to the system naturally and bring the pH down. What sort of gravel are you using, or did I already ask that?

urbanrunoff
05-07-2010, 07:45 AM
the original system uses gravel
my secondary system uses hydroton and nfts

jackalope
05-07-2010, 09:55 AM
I struggled with 8.2 water for a long while, I could never get it to come down .... so I gave up on it for last year .... if the snow ever quits falling and the weather turns warm, I may have to haul my water from Lewistown (99%pure, purest water in the country!), but first I will measure it and see what the PH is ;) I haul my drinking water from Lewistown anyways, because it tastes so good .... better than the "swamp water" we have here in Grass Range :!:

urbanrunoff
05-07-2010, 02:39 PM
yeah as i said the guy who lives 2 blocks from me said only way to get it down is RO'd water (if using water from tap).
Makes me wonder how hard our water has to be in order to buffer it up like that.

badflash
05-07-2010, 05:57 PM
Many municipalities use sodium hydroxide to protect their pipes. Acid is the only way I know to deal with that. It goes through an RO filter.

urbanrunoff
06-12-2010, 06:25 AM
what a score!
i got a free RO system from a friend who had it laying around in their shed. It is a hydroponics/garden system with pump and hose hookup.
Unlike the one's for under the kitchen sink this thing is HUGE and heavy.
the filtered water has a pH of around 7.2! (8.5 coming out of faucet)
But it has ammonia about .5 ppm (probably by the fact that chloramine is not entirely filtered out and the ammonia is what's left)

If i add vitamin C will that do the trick or does that only work when ammonia is part of the chloramine compound?


also, what a waste of water, i'd say it 2/3 go to the lawn.


ps: GO USA! show those brits how to play soccer.. :)