I’ve recently purchased an R.O filtering unit Due to my hard water issues and have noticed that the R.O water has a PH around 9. I have been running a TLO setup for couple years and never had any PH issues with regular tap water but due to the high mineral content was experiencing scale on my fabric pots and slowed/stunted growth, which lead me to get the R.O unit. My question is should i be concerned with a PH level of 9 in a Notill TLO setup? Should i be lowering my PH with lemon juice or Vinegar?
My only concern is how lemon or ph down solution will affect my microbial life ive heard mixed opinion on PHing solutions in TLO grow.
is your ph meter working properly? ro water tends to acid because all the mineral content, "hardness", is removed in the process. verify your meter or get some aquarium test strips for ph and hardness which is a close enough test for organic needs. edit: unless you have a tds meter you might opt for the aquarium test strips. all these strips do is give an indication of the waters state. they in no way are intended for high level of accuracy. it occurred to me that perhaps your ro unit is not working properly. the strips will indicate "hardness" on a scale. your ro water should be hardness neutral.
I do have a Blu PH pen and TDS meter after going through the R.O unit the water reads at around 40ppm and PH around 9. Good idea on the strips ill have to test and see if i get same results as i am with my pen. My pen should be working properly ive had it calibrated recently and havnt had any issues prior to using R.O. Ive heard that R.O water tends to confuse meters because there arent enough ions in the water after filtration but im no expert on the science behind that.
that's interesting for sure. it's just so bizarre because water "hardness" (total carbonates), is what raises the water ph. typical ro units are rated to remove ~90% of minerals (includes "hardness). your filtered ro water has 40 ppm of something and that surely isnt enough to raise the ph to much above 7.0. if you have 40 ppm following ro and if the unit is at 90% efficiency then you started out with water in the ~400-450 ppm range. maybe verify that for ro efficiency against your meter. it's said that a properly ro-ed glass of water that tests at 7.0 will drop to ~5.0'ish within a couple of hours if left uncovered simply due to dissolved co2 in the air. with your high ph reading something is amiss. the test strips will verify your ph meter's accuracy. there's a huge color difference between yellow and blue (or whatever the test strip panel indicates). all else being equal your ph meter is off in this case. occam's razor thinking. let us know after you get the aquarium strips
Well you’re calculations are right on my friend ....tap water prior to filtration was right around 425ppm, not sure what solids/minerals were present because surprisingly never had any issues till my 4th-5th run in same pots(No-Till). Being new to growing i didn’t know how hard water affected plants otherwise i would have purchased R.O unit couple years ago when I first started....Wow I was not aware that the PH would drop just from leaving the bucket uncovered that’s crazy pretty dramatic change. My tap water used to read right around 7 before R.O. .... thanks for the info I will be letting my water sit uncovered before i try taking reading next time and will definitely follow up with strips as well. Sent from my iPhone using Grasscity Forum
@BrassNwood deals with high alkalinity water of 8.4'ish iirc. he uses elemental sulphur in his soil to reduce the alkalinity (carbonates, i.e. "hardness") with great success as i understand it. for a no-till, high alkalinity water situation that might just be what you need. i reckon he'll be along directly now. hth.
Vinegar will do but it a weak acid. Sulfuric is best but hardest to handle and work out ratio wise. Living in the Desert Southwest an RO system don't make much sense as it wastes so much water for every gallon it makes. Besides I use a tremendous amount watering the yard and flower beds every few days that the Cannabis has to be treated like everything else. No Special favors LOL. I water right out of the hose and the city pushes the PH up to 8.5 to help protect the old iron main water pipes. After the second full season my plants started showing signs of all that alkaline water as the soil PH keeps creeping up over time. Adding Sulfur is the path I chose to push that soil PH back down and it worked almost as fast as a started adding it. At veg to flower transplant time my permanent outside spots get dug out and at that point I add a tablespoon of Sulfur and a pound can of Chicken manure to the dug out soil. I drop the vegged plant in the hole and backfill with the amended soil I just dug out. Move to the next hole and repeat. When it comes to mixing a batch of new soil I omit the lime and add Sulfur dust @ 3 tablespoon per Cubic Foot of soil mixed. BNW
Luckily i was able to find some strips and a liquid test kit from while back, after testing with both the strips and the liquid im getting colors matching a ph in the 7-8 range which sounds alot better than the 9-9.5 i was getting with my meter. I let the water sit out for couple hours and before using the strips gave it one last try with the pen and it gave me reading of 9.4. Maybe what i heard about ph meters having difficulty reading R.O water is true. Sent from my iPhone using Grasscity Forum
good job man. at least you have a better handle on how you might address things going forward. also, those big no-till beds need to be treated like outdoor raised beds and the associated maintenance considerations folks give them i think. good luck and bountiful harvests!
Yes sir! Started Growing soon as my state went Rec few years ago first grow was a bottled “organic” grow with decent harvest/results. But after stumbling across the True living Organics with the Rev and digging around the interwebs i was sold on this technique it just makes sense to work with nature instead of against her and lettting your plants decide what they need rather than force feeding them. Currently running 7gal smart pots 3rd generation soil in a 4x4 Tent flowering under a HLG 550 using AACT along with top dressings covercropping/mulching ive had great results so far but always trying to make improvements. Thanks for feedback Good luck and bountiful harvests to you aswell!
Might have to give that a try in my outdoor garden this upcoming season because I will be watering straight from my hose also. -Thanks
" What Are Some of the Difficulties with Pure Water pH Measurements? The low conductivity and limited buffering capacity of low ionic strength pure water causes pH electrodes to drift, producing non-reproducible and inaccurate results. The common problems are large drift, unacceptable flow sensitivity and poor temperature compensation. Electrical noise and interference complicate matters further. Certain properties of pure water adversely affect the ability to obtain a reliable pH measurement. For many years it was believed that these properties could not be satisfactorily overcome in order to achieve the desired measurement accuracy and reliability. The areas most affected by the pure water properties include: Reference Electrode Stability Glass Electrode Response Electrical Noise Special T.C. Requirements " Source for more in-depth reading. www.yokogawa.com/library/resources/white-papers/understanding-ultrapure-water-and-the-difficulties-with-ph-measurement/
Nice so it is true, thanks for the info. I will not be killing myself trying to calibrate my pen Sent from my iPhone using Grasscity Forum
@BrassNwood Very interesting info regaring sulfur. I keep hearing good things regarding sulfur and its abilities to help with terpene production as well. So I have a question, does the sulfur do something similar to lime which is why you omit lime in place for sulfur? Could you use both? And if so, when would you? Sorry for the 20 questions I just learn so much from you guys and want to make sure I have things down solid in my mind for future reference.
Ive never heard sulfur can increase terp production thats pretty interesting. i think i have some sulfur in my town tap water maybe thats why my flowers smell/taste so good haha.
I have always used gypsum, ( Calcium Sulfate), as a sulfur source for helping terps. In my situation, I don't need the sulfur for pH reasons. I do this for veggies as well as cannabis, and in my opinion it helps a lot. Composted chicken manure can be another good source of sulfur, (which I also use) if your goal is to merely aid in terp production. Depending on your geographic region, this may be easier to source. I have heard that both elemental sulfur and gypsum can be tricky to source in places with native soil that doesn't typically need it. cheers os
Ill use gypsum, but sparingly usuallyas a top dress i feel it helps combat compaction and keeps my top soil nice, loose and loaf. Never used it to specifically add sufur to my mix but good to know thanks man. Sent from my iPhone using Grasscity Forum