question about a test

[Sundiego]

Is a TDS (total dissolved solids) meter, the same as measuring the hardness of the water?

Thx NOOB

 

[Kurt_Nelson]

Kinda... but not really.

From my understanding (correct me if I'm wrong water gurus), a TDS meter measures exactly that: Total Dissolved Solids.) The TDS reading in ppm is not discriminate of what it's measuring. The solids could be Calcium, it could be various nitrate compounds, it could be copper and lead from really really bad piping. It's pretty much whatever is in the water. If you're measuring the TDS of your mixed salt water, you'll be even reading the salt level too.

Hardness specifically deals specifically with the levels of certain calcium and magnesium compounds in the water. Hardness doesn't really care about all the other junk.

Generally though, hard water will have a high TDS reading while soft water will have a low TDS reading. To measure hardness in your aquarium water, you'll want a KH/GH test kit.

 

[Sundiego]

Can you recommend a good KH/GH test?

Thx Mark

 

[Phyl]

A TDS meter will max out well before it measures the TDS in our tanks. After that they just read "ERR".

We use Salifert test kits for all parameter checking. They're a good mix of reliable and affordable.

 

[lando]

From my understanding (correct me if I'm wrong water gurus), a TDS meter measures exactly that: Total Dissolved Solids.) The TDS reading in ppm is not discriminate of what it's measuring. The solids could be Calcium, it could be various nitrate compounds, it could be copper and lead from really really bad piping. It's pretty much whatever is in the water. If you're measuring the TDS of your mixed salt water, you'll be even reading the salt level too.

Apples and oragnes. Hardness and TDS are a bit different.

 

[Sundiego]

Is KH the same as Alkalinity? I am looking here:
http://www.marinedepot.com/ps_ViewItem~idProduct~SF1123.html



I bought this test kit a few days ago and it has alkalinity, as one of the tests.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=ADME:B:EOIBSAA:US:31&Item=7762903275
I am assuming this takes care of the KH/Alkalinity?


What about GH?

I am also going to get a kit for calcium, and magnesium, am I missing any other tests?

I am new to this.

Thx Mark

 

[Kurt_Nelson]

Yes... kH and alkalinity are the same.

Yes... that kit will test for alkalinity just fine.

Regarding GH, from my understanding, that's just the freshwater equivalent to KH. If you wanted to know if your tap water was soft or hard, you'd use the GH test.

Ca test is good to have, but not required if you're not doing corals right away or have anything that requires calcium. In my opinion, it's still a good thing to know.

Magnesium testing isn't really required, unless you're dealing with Ca issues. Low levels of magnesium can effect your Ca levels. However, with normal PWCs you should never really have to worry about Magnesium levels. I'd probably put off the Mg test kit unless you're anal like me and want to know exactly what the parameters of your water are.

 

[Sundiego]

Thanks Kurt that really clears things up.

I guess I wont need the GH test as I have a soft water system, then the soft water goes through my RO/DI unit.

Thanks again!

Mark