Best way to raise hardness

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WhistlingBadger

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Hi, Kids. I'd like to raise the hardness in my rainbowfish tank a couple degrees. I've been using epsom salt for the past couple years, but it doesn't have any calcium and leaves the KH very low. Wondering if there is a better way. Ideas?
 
Move to Santa Barbara :p
Funny you mention that. Our town water is very soft, but our well water is off-the-charts hard, something like 65 or 70 degrees hardness. I've thought about just adding a bit of my well water to the tank...
 
Funny you mention that. Our town water is very soft, but our well water is off-the-charts hard, something like 65 or 70 degrees hardness. I've thought about just adding a bit of my well water to the tank...
Your well water should be chemical and pollutant free, but be careful. Take it slowly a little at a time until you get the feel for what it is doing in your tank.
 
Buy a water hardness test pen, I use one when mixing my RO water and tape water. I have a TDS-3 which is very accurate and cost me around 10 USD on Ebay. It is also very easy to use.
 
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Funny you mention that. Our town water is very soft, but our well water is off-the-charts hard, something like 65 or 70 degrees hardness. I've thought about just adding a bit of my well water to the tank...
That may be a good idea if you do it carefully - yeah our water is really hard.
 
I have a TDS meter that I use when adding epsom salt, so I'm familiar with the process. I suppose using well water would follow the same process, and yes, it would pay to be careful. I think I could pave driveways with this stuff.
 
I've been using epsom salt for the past couple years, but it doesn't have any calcium and leaves the KH very low

Mix some gypsum with your Epson salt. Gypsum is calcium sulfate. Roughly 3 parts gypsum to 1 part epson salt. Same basic ingredients that are found in commercial GH boosters such as seachem equilibrium. Other common ingredient are calcium chloride and magnesium chloride. I personally use RO water and use a mix of magnesium sulfate and calcium chloride. Plants and animals need sulfur and chlorine as well as calcium and magnesium in the water. Tap water does has some chloride salts in it (byproduct of the chlorination process) while RO Does not. So for my RO water a mix of epson salt and calcium chloride is the better option.

Note: chloride salts are safe in an aquarium. pure chlorine and chloramine are not.

All of the ingredients I have listed can be found on line and in some stores. I got what I needed from LoudWolf.com and amazon.com at 99% purity levels. Using a pure product is better since you don't want perfumes, dies or other ingredients that might be harmful to the fish. Also pure gypsum and Epson salt dissolve rapidly in water which would allow you to increase your GH to whatever level you want.

calcium and magnesium sulfides and chlorides will never register on the KH test because ty are not carbonates. calcium and magnesium carbonates are the common sources of KH in tape water. Unfortunately they don't dissolve easily. unless your aquarium water has a lot of CO2 in it or your water PH is below 7.. But you don't need KH for a healthy aquarium or PH control. You can use a a decorative snail shell instead. Snail shells are primarily made from Calcium carbonate. It won't dissolve easily if the water PH is 7 or higher but if the water gets acidic for any reason the shell will react with the acid to neutralize it and return the water PH to about 7. The snail shell will normally not add much if any KH but it does have the sam PH stabilizing effect calcium and magnesium carbonates do

Many people also use sodium bicarbonate or potassium bicarbonate to increase KH but you have to be carful with them. They dissolve easily and and you have to be careful. If you add too much the PH will exceed 7 and could go up as high as 9 or 10.
 
I have RO water and I remineralize it with magnesium sulfate and calcium chloride.
Calcium chloride can be purchased at pool stores in 5 pound buckets for about 10$

You want to mix the mag sulfate and calcium separately as they will bond and be difficult to dissolve.

As mentioned gypsum salt works as well.

I use rotolabutterfly.com dosing calculator to figure out my ratios.
 

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