Water Hardness

[Winged]

This is something that seems to nearly completely confuse me.

I understand that it has to do with calcium in the water. I also know that Louisville water (we live near Louisville, KY and get our water from them) is very hard and leaves lovely little calcium deposits on my all my tanks (not just my fish tanks, but also my water dragon's tank, my frogs' tank, and especially my turtles' tank). (It is bad enough that I frequently will take a rag dipped in vinegar and wipe off the outside of my fish tanks and the inside walls of my non-fish tanks.) I also know that certain fish (I believe most of my fish) need softer water than what we have. I think I also understand that peat can be used to soften water (is this correct?).

What I don't understand, though, is how to interpret reading it. The test strips (I know they're not very accurate, I'm getting the other kind of test soon) tell me the hardness is 300 ppm (which stands for what?). When I look at the Louisville Water Company's water report, it says, "Usually when hardness is lower than 60 mg/l the water is 'soft.' When hardness is higher than 180 mg/l the water is “hard.” LWC water is moderately hard, at 165 mg/l. That equals 9.6 grains of calcium carbonate per gallon." I don't buy that LWC is "moderately hard". In town, where I work, I've tested the water. The strip shows the water being as hard as the strip is capable of showing. When I test water at home, it's a little lower than that, but not much. But, I'm not sure how the reading of 300 ppm compares to LWC's reading of 165 mg/l.

I've tried reading up on this, and just get confused when they start talking about GH and KH, which I discovered today stood for general hardness and carbonate hardness, and when they start talking mg/l, mainly because my test kit uses ppm.

Can somebody please take the time to explain this to me?

Thanks very much! (And I apologise if this thread was difficult to read.)

 

[shawnhu]

http://www.thekrib.com/Plants/CO2/khgh.html

This read might help. I'm not an expert in it either, but people use different scales to measure gH and kH. Just like how the US uses feet/miles, and the rest of the world uses meters and kilometers.

General Hardness(gH) is the concentration of calclium and/or magnesium. Karbonate Hardness(kH) is the concentration of carbonates and bicarbonates. (I know Karbonate is spelled wrong). General Hardness is usually difficult to cahnge, without a Reverse Osmossis system. Karbonate Hardness can be changed through several ways. Some that I am aware of is crushed coral, Sodium Bicarbonate(Baking Soda), Peat Moss, Cuttlebone, Dolomite, and many chemicals that is marketted in our hobby.

I hope this has helped, but take your time, and don't rush into things and it'll come together sooner than later.

 

[Canuck]

I think I also understand that peat can be used to soften water (is this correct?).

Yes, many keep peat in their filter and pretreat water with peat.

What I don't understand, though, is how to interpret reading it. The test strips (I know they're not very accurate, I'm getting the other kind of test soon) tell me the hardness is 300 ppm (which stands for what?).

Parts per million

When I look at the Louisville Water Company's water report, it says, "Usually when hardness is lower than 60 mg/l the water is 'soft.' When hardness is higher than 180 mg/l the water is “hard.” LWC water is moderately hard, at 165 mg/l. That equals 9.6 grains of calcium carbonate per gallon." I don't buy that LWC is "moderately hard". In town, where I work, I've tested the water. The strip shows the water being as hard as the strip is capable of showing. When I test water at home, it's a little lower than that, but not much. But, I'm not sure how the reading of 300 ppm compares to LWC's reading of 165 mg/l.

ppm stands for parts per million and mg/l is mg per liter. Essentially the 2 measurements are equivalent since there is a million milligrams (mg) in a liter of water. Metric is a wonderful thing. Test strips are awful, I'd pretty well guarantee you the test strip is wrong.

I've tried reading up on this, and just get confused when they start talking about GH and KH, which I discovered today stood for general hardness and carbonate hardness, and when they start talking mg/l, mainly because my test kit uses ppm.

gH is a measurement of the magnesium and calcium content of water (general hardness). This can be important when trying to breed different types of fish. kH as you have learned is the carbonate hardness of your water. The most important aspect of this is it is used in the nitrification process and can be depleted causing pH swings. The pH swings themselves are pretty well meaningless but this also signals the build up of significant organic pollution which will have a detrimental effect on the health of your fish. Hope this helps

 

[Winged]

Thanks both of you! You both helped me understand a lot better.

Canuck, I am getting an API master test kit tomorrow and will retest the hardness tomorrow to figure out what it really is. I've been wanting to get rid of the strips for a while, and I'll be using my last one tonight. The drop tests last much longer and I know they're suppose to be more accurate, and I have an awful time reading the pH on the test strip.

Shawnhu, you mentioned several ways to change the kH, and mentioned cuttlebone. How well does cuttlebone work? I always have a piece or two floating in with my turtles, and always have plenty of extra on hand. I'll have to test their water tomorrow when I get my new test kit.

Thanks again!

 

[Canuck]

Crushed coral, cuttlebone will increase gH and kH. Sodium Bicarbonate(Baking Soda)and (I believe) dolomite will increase kH only. Peat Moss will decrease kH and gH. the chemicals that are marketed to reduce hardness or pH are generally counterproductive.

 

[KarlTh]

Dolomite is another form of calcium and magnesium carbonate and will raise both KH and GH. Not by much though; it barely dissolves in hydrochloric acid, never mind water.

 

[Winged]

Good to know, both of you. Thanks again!

 

[colinsk]

Crushed coral, cuttlebone will increase gH and kH. Sodium Bicarbonate(Baking Soda)and (I believe) dolomite will increase kH only. Peat Moss will decrease kH and gH. the chemicals that are marketed to reduce hardness or pH are generally counterproductive.

How does Peat Moss work? It is very easy to lower KH but I can't think of any easy ways to lower GH. What am I missing? Does Peat Moss attach to Ca and Mg?

 

[KarlTh]

Yes, although not that much. My GH drops from around 120ppm to 100. It's not an amazing drop, but it's definitely real. At the same time the pH drops a good point.