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Filtrating Nutrient Water, Good or Bad?

I was reading “Complete Guide for Growing Plants Hydroponically, J. Benton Jones, Jr.” and read this “Filtering the nutrient solution is not a common practice, nor is it recommended in most of the literature on hydroponics. The only exception would be water dispensed through a drip irrigation system”

After recently installing a RO system with UV filters i’ve been adjusting my nutrient formula (Current Culture Nutrients, Ebb&Flow) to adjust for deficiencies from the RO.

I am still adjusting quite a few controls since I just moved into my new building, but I started thinking that the sediment filter I installed on my Ebb&Flow might have some effect? My daily ppm’s are pretty consistent.

I haven’t heard of any reasons why you wouldn’t filter Nutrient Water before, and the reading from J. Benton didn’t elaborate any further.

Does anyone know of an adverse affect from these filters on nutrient water?

I haven’t been able to finely tune my nutrient formula enough to account for not using well water.
I am using Current Cultures nutrient line with their CoCo Cal, But at their recommended dosage I still seem to experience slow growth, and yellowing of the lower leaves in veg (Leaves are not hidden or yellowing from a loss of light)

In Ed Rosenthal’s Growers handbook he states the water must be brought up to 150ppm. I seem to be around 80ppm using the general recommendations from Current Culture.

Anyone else have a baseline ppm for Ca-Mg when using 0ppm RO water?

I really appreciate any feedback, These forums are amazing :slight_smile:



I would definitely bring your cal-mag ppm up to 150-200 asap @denavici. That’s way to low for RO. I ran into this problem my 1st hydro grow.
Also I can see the benefit of filtering your nutrient solution to help keep your drippers free flowing as long as possible. They get residual buildup pretty fast and require frequent maintenance to keep them flowing. I prefer DWC myself.

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Excellent, Thanks for the feedback @Tygrow78.

I have been trying to adjust my ppm’s to what I was used to before using RO water, and since I never had to use cal-mag I didn’t want to add too much.

This is also the first time I can completely control the temperature to under 80 while also running CO2 and my lights. Being in a cooler environment with less evaporation I think makes the deficiency worse.

I’ve been thinking of trying a RDWC in my 3rd room. The last few months i’ve been experimenting quite a bit on different plants and loved the results.
I have a few DWC buckets in the corners of my Ebb&Flow room, I just hate to have to fill each DWC bucket individually.

At the peak of their growth cycle, in 5ga buckets, aren’t they drinking quite a bit everyday?
Both of the tomato plants I grew in 5ga buckets over the summer got 6’ and were drinking 2-4g a day.
How often do you check the EC and PH in each bucket?


I have to ask,are the RO systems still 1:3? Cuz last time i ran an ro set up it would only filter and keep at a 1:3 ratio meaning i had tons of water waste to run somewhere else away from my building. I was filling up 200 gallon tubs then too. Way too much waste. Also,ive never filtered my nutrients, but wonder why you would. Nuets are made up of salts basically and thats what builds up and creates clogs and such,but thats 1 of many reasons why you incorporate a flushing cycle to wash away any built up salt deposit on your roots or in your equipment. I like this tooic a lot. Some people have no clue how important the quality of their water is to the plant. They just figure if they can drink it that it must be good to use. Hahaha

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Filling the buckets can be a little tedious some times @denavici. My 3 buckets in my Veg tent drink a gallon a day, then my rdwc setup has 3 buckets that drink 2 gallons a day during flower. I mix 5 gallons of nutrients at a time in the blue plastic jugs. I have a top off reservoir I dump the 5 gallons into, and it fills up to my settings. Draining the system every week, flushing my roots, then filling it back up takes a good hour or more.
But all the extra work pays of in the speed of growth, and the size, quality, taste, and smell of the flowers.
If you have your system all dialed in, of course…
I run continuous Ec and Ph monitors and look at them regularly throughout the day. I did pens at 1st, but they’re very time consuming. I’d rather just glance at my wall real quick.
Congrats on getting your temps down my friend! It can be stressful to know your plants are in a hot environment. My last lights I ran were hot and I struggled with 85-86f temps for a while. I get it.

I’ve never heard of filtering nutrients before either and not sure why some one would @bullfrog420. You must of been running a pretty good sized drain to waste setup to go through that much h20.
I personally don’t have my own RO system yet, but need to purchase one before my move to a bigger place. As far as I know that’s how they still run, 1:3.
I just go to a store that let’s you fill 5 gallon jugs curbside 24 hrs, and it’s $2.50 for 5 gallons. But will be losing easy access to it soon. I’m big on flushing my roots between each reservoir change. I take extra care of my rootzone on all my grows now. I kind of neglected that my few grows.

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