Thinking of coming into the 21 century

I’ve never checked ph or tds or ppm I’ve always grew outdoors caveman style .Now im indoors and need to check theses things so i’m told. PH i get looking for ideas on a meter around $50 and is tds really that important growing in soil and do they make meters that do both . Keep in mind i’m an old recluse and i still have a flip phone i got from government so if you can explain with crayon drawings and interpretive dance @bob31 @Countryboyjvd1971


Just posted this in another thread.


That’s a great meter but 3x more than the op wants to pay. I saved a couple let me look and see what I have saved on my computer.


Thx this is all new to me

It’s $54 but it has no reviews so it must be new.

I would rather see you go and get something like this:

ph and tds meters

ph up & Down

1500ppm Calibration Fluid for TDS Meter

7.0 calibration fluid for pH Meter

You need the pH up and down to adjust the pH and the calibration fluid verifies the accuracy of the meters.

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So exactly what does a tds meter read and why do i need to check tds

A TDS Meter reads the amount of Total Dissolved Solids in your water. The meter measures the TDS in PPM or Parts Per Million.

The first step is to draw your tap water and leave open to allow any chlorine to evaporate for 24 hours before using.

Measure the TDS of your water. Water your plants and allow for abut 20% runoff. Measure the TDS of the runoff. This measurement will let you know how much nutrients are left in your soil. If the levels are below the levels prescribed on your nutrients feeding chart, then you start giving the plants nutrients on their next watering.

When the TDS is low enough to begin feeding nutrients

You would draw your water as above, add the nutrients per the nutrient feeding schedule, then check the TDS. Water/ Feed your plants and allow for abut 20% runoff. Measure the TDS of the runoff.

This last measurement will tell you how much of the nutrient mix was consumed by the plant through the soil.



@Rexx it is what gives you an indication off how much chemicals and micro particles that are in your water that you will use to feed the plants. And welcome to the forum Sir.

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@Rexx let looks like @bob31 Has you pointed in right direction
Ph is the most common issue with indoor grows
So yeah a decent meter is important
Im with @Rugar89 is a meyer with replaceable probes
And use a similar meter ti his but as bob pointed out they are not cheap the meters he posted and will take care of your needs


The ones I posted are more budget friendly if nothing else, lol. I have my eyes on this baby


@bob31… wasn’t there an apera that was in the 50 dollar range?.. I think Apera had a replaceable probe unit for 75


@Rexx you will most likely use your Ph meter TDS meter or PPM its actually the same thing, the ppm meter can be bought for a good price on Amazon but you would be better off paying a little bit more for a PH meter it’s so well worth it.

The Apera for $50 is only a pH meter @Zombo


ph and ppm arent the same thing
Ph is how acidic your water is
And ppm is the readings that a tds meter reads
Tds stands fir total dissolved solids and ppm is parts per million
Just wanted to clarify this for everyone


This gave me a laugh this morning lol. These guys have you covered!


I ment you could switch from one reading to another on the meter and it’s really just the American way off reading it and the European way I was sure anyway but I stand corrected @Countryboyjvd1971.

Me too mate you need some humour @MattyBear.


Be careful when using PPM. What those meters really measure is EC (Electrical Conductivity) and then they perform a calculation to give a PPM value.

Unfortunately there are two ways to convert EC to PPM, they scale by a factor of 0.5 or 0.7, it depends what the manufacturer chose. My Blue Labs TDS meter gives me the option to use the 0.5 or 0.7 standard

For example:
EC=1.0 conversion factor 0.5 => 500PPM
EC=1.0 conversion factor 0.7 => 700PPM

When comparing PPM figures make sure you know which conversion factor both meters are using (yours and theirs). If not certain use EC otherwise you aren’t comparing apples with apples

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I have my grow bags in small plastic wash basins to keep down on mess can i test the water in the basins of ph and tds Im operating out of a wheel chair so lifting is tricky.

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Yes you sure can… just make sure to keep the plastic basins clean and free of salt/sediment build up from runoff that could foul your ppm/EC reading… i shop vac mine out because i cant lift my plants either, they are in forever positions lol… @Rexx

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