Is this TDS meter good?

[ajremington68]

Is this a good TDS meter? (Amazon)

HM Digital DM-1 In-Line Dual TDS Monitor, 0-9990 ppm Range, +/- 2% Readout Accuracy,Blue & White​

https://a.co/d/h4Z4hMq

And is this a good meter? (Amazon)

TDS Meter Digital Water Tester, Lxuemlu Professional 3-in-1 TDS, Temperature and EC Meter with Carrying Case, 0-9999ppm, Ideal ppm Meter for Drinking Water, Aquariums and More​

https://a.co/d/2bh37qc

What are the differences? One hooks up to your rodi the other doesn't? Is the handheld any good for the price? A lot of the reviews of the handheld refer to people testing tap water, has anyone compared a handheld to a TDS that hooks up to a RODI unit, are they comparable? Have not tested my TDS and my unit is about 5 months old and want to as I bet it's time to change out some filters.

 

[Mr. Mojo Rising]

I bought a cheap handheld TDS meter from amazon for $15, it has worked fine for me for years. I don't think its complex technology, so any any cheap unit should do. I use it so rarely, maybe once a year (after all why would you use it often?), I just don't think its worth spending much money or thought on (though others might have a different opinion).

 

[ajremington68]

I bought a cheap handheld TDS meter from amazon for $15, it has worked fine for me for years. I don't think its complex technology, so any any cheap unit should do. I use it so rarely, maybe once a year (after all why would you use it often?), I just don't think its worth spending much money or thought on (though others might have a different opinion).

how often do you test your RODI unit?

 

[Mr. Mojo Rising]

how often do you test your RODI unit?

Almost never. I figure why should I? If it reads zero the first couple of times I use it, it will always read zero. Every time I’ve randomly checked it has showed zero. My tap water reads .178 so I know it works. There is enough to worry about in this hobby, this is not a consideration to me at all.

 

[Buckeye Hydro Verified Sponsor]

With a RODI system, you want to know the TDS in THREE locations

• tap water
• RO water
• DI water

So no, I'd not recommend the DM1 to you. This is a meter we recommend for RO systems, not RODI systems.

A better choice would be the TRM1 - a THREE probe meter.

Russ

 

[F4u-SuperCorsair]

how often do you test your RODI unit?

Every time I make fresh water. I throw away the water until the meter says less than 10 tds.