Meters meters everywhere meters


I’m clear on Ph meter readings for hydro and soil
But what about all these other Meters?

Is there one that does it all?

Since I’ll be doing hydro this time,
what meters should I have and why?
What numbers am I looking for

You need a good quality PH meter, a good quality PPM meter, and something to measure the temperature of your water (normally a good PH meter also has a thermometer on it).

Other than that you need the same stuff as if you were growing in dirt - a hygrometer or something to measure ambient air temps and humidity. Both Blue Lab and Apera make combo meters (very expensive).

Don’t go cheap on the PH Meter. It’s a critical tool for hydro and you want something that is accurate, waterproof, and easy to calibrate.


When I get a new meter I always check against a good liquid test kit. My $15 Amazon one is reasonably accurate. And I still test with drops once a day just as a sanity check. The TDS/ec meter i picked up, seems right, also a Amazon 15 dollar unit. Stick it in tap water, get shocked I’m not like someone in Flint, stick it in RO water and remember why I have that filter. It also does temperature in C and F.

I think those are the main two hydro meters to start with.


Apera Instruments PC60

Just bought this


I know where I should be with Ph.
Where should I be with ppm/tds?
The info here makes those 2 sound iinterchangeable BUT I read an article that said they absolutely were not. So I’m confused.
If I’m not mistaken I should be at:
Water temp 70
Tent 80? Day - 70? Night

PH 5.8
Ppm 1050?

Anyone else?

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What are you feeding her or planning of feeding
Here something i found for you originally posted by @garrigan62

Start with 600 PPm for week 1
900 PPm for week 2
1200 PPm for week 3
if you go over 3 weeks veg
1500 PPM week 4
1800 PPM week 5 and hold there
at bloom I flush and go to 1000 PPM week1
1300 ppm week 2
1600 PPM week 3
1900 PPM week 4
flush weekly…VERY IMPOTANT
and hold there until last 2 weeks and ad your bloom enhancers if your using them
this is double secret probation info…

Those are soil readings I believe… I’ve never been over 1200 ppm on my strongest feeding plant in hydro … :wink:
I would say
100 to 300 for seedlings and cuttings
300 to 500 mid veg
500 to 700 heavy veg
700 to 900 early flower
900 to 1100 mid flower
800 to 1000 towards the end of flower
I would say to stay at the lower side of those ranges until your plants start asking for more… :wink:

:v: :sunglasses:

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Two different answers🤔
@Countryboyjvd1971 is yours for soil or hydro?

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Soil are you asking for hydro @Fairieswear8oots id so fo with peach fuzz

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Bromothymol blue chemical test for pH and Myron L DS meter and calibrating solution for PPM and you can’t go wrong! Methyl red picks up where Bromothymol blue peters-out. (FYI)

P.S. I like needle meters when it comes to electronics too, they have “bounce” not digits scrambling around on a screen that won’t settle down.

Your 1st pic didn’t work
Also, as a Laman/newbie I’m not sure what any of that means

Thank you @peachfuzz & @Countryboyjvd1971!
I’m doing hydro this grow, but keeping a separate note book for soil, so both are needed and appreciated!!:v:


What about tds and ec levels?

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@Fairieswear8oots just to be clear im a soil grower so when im asked a question I always think soil
Glad your trying hydro
I haven’t made that commitment yet

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@Countryboyjvd1971 will do :+1:
Is the tds, ec needed with a soil grow and if so what are the numbers to look for

Tds/ec is absolutely necessary for a soil grow. As someone who has issues with hotsoil, a tds/ec pen allows me to test my soil, then adjust my nute routine to fit what my plant needs, tds/ec wise. It helps rule out or confirm various issues. I feel like I understand my plants’ needs & my soil’s condition so much more with my ec pen.

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@blackthumbbetty Thank you!
What numbers should I look for in soil?

I’m gonna stay with GH flora trio

I am not an expert, at all. I follow this as a guideline. Several others out there seemed to recommend the same, so I figure this is fairly accurate?

If anybody reading this thinks it’s bad info, please let me know so I don’t kill my plants! :grinning:

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Thank you love!!!

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