Tds... what , why

OK been told I need one. Why and what does it tell me? Getting together equipment for 2nd grow.
2x4x5 vivosun tent w/ vivosun 4" in line speed controlled fan, carbon filter, HLG 260XL LED LIGHTS, FFOF soil, 5gal pots w/ drainage trays, apron 1209A PH meter w/ up/down adj., timers, tie down tubing,
Tds meter??? Why?
Nuets for bloom stage
Suggestions needed so I don’t miss anything.


TDS stands for Total Dissolved Solids. Another way to state that is in PPMs or Parts Per Million of your feed/water solution. You want to be able to keep track of these numbers so you know how much you are feeding your plant and if a problem arises, you can test the PPM of the runoff and see where you’re at. You will need to feed at the proper ph of your medium to make sure your plants can uptake the nutrients you give them. :v:


Using FFOF (if I understand correctly ) I “shouldnt” need any nuets till flower stage, if correct I would appreciate any suggestions on brand and names of the right stuff to be used then. Still not clear what I’m measuring and why. Are these measurements just a guideline or a specific reading I would be trying to achive?


In soil a TDS meter is useful for determining if you do need to feed or if any issues develop can be used as a diagnostic tool. It is correct that in general you won’t need grow nutes in FFOF and supplemental P and K in flower will certainly help but may not be necessary, depending on the strain, size of plant etc.

So here’s an example: plant looks a little yellow around the edges. Water with distilled water to runoff, take a sample from the last 10% and the number is 1,000 PPM (TDS). That would tell you that there is a lot of dissolved minerals present already and that your issue may be over feeding causing a problem. Same test and the result is 200 PPM. Time to add a bit to make sure your plant isn’t hungry.

I’ve simplified things to give a couple of concrete examples of why a TDS meter can be useful. Mixing supplements can be done more precisely, you can check status of muni water, mix nutes to a target number, etc. It’s a cheap instrument and will be used frequently.


Well said @Myfriendis410 :wink: thanks bud


Ok, that’s a lot of help, thanks. I have an idea now, I can re-read some of the info on this with a better idea of what I’m reading. Thanks so much. I get a little dense sometimes, and the bowl didn’t help either. LOL.


It never does for me either haha!

There’s a lot of nuances in this indoor growing. That’s why most of us recommend only one or two plants to start so you can really understand the life cycle. I’ve been doing this for years and I STILL don’t know what I’m doing lol.


check out the free growing guides here. This site is wonderful that way.

search, read, and you will save yourself a world of grief, monetary loss and frustration with no positive results.

Best Wishes…:cowboy_hat_face::vulcan_salute::v:

Plans are for two plants. Gonna play with some LST and maybe scrog. Not sure but one plant scrog may out produce 2 non-scrog (so I’ve read) some recommendations on a TDS meter would be appreciated. I have the 1290A Aperia for pH so some thing comp. to it value wise, spent 50.00 on PH. So some where near that max.

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Any $15 meter will work fine. Measuring PH is a little more difficult.

My experience with the SCROG is increased yields around 15%. FYI

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Hmm mm 15% …is there to room in a 2x4x5 tent for 2 plants scroged?

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The footprint I have for a SCROG is 22" X 36" so I would say only one plant would fit comfortably. You can do smaller plants and more of then (SOG) but the footprint is the footprint; you can’t pull more than “X” amount from that amount of space.

And that 15% is a guess. I’ve run plants out side by side and assuming you did your training on a supercropped photo, did the job perfectly etc it will only make a difference of an ounce or two at most. I usually see between one and two ounces over an upright plant. It’s worth the effort but it’s not a revelation either.

That will take some thinking, I do have room for 2 plants with some limitations (non-scrog)

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I like the SCROG: it’s my preferred method. One benefit with this is I get less trim and larf and more useable flower. So it might be more that there is a similar mass of plant material but biased more toward flower than sugar leaves and popcorn.

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