Difference In Kh And Gh

Blueberrybetta

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can someone help explain the difference between KH and GH and which one i look at for a betta or do i look at both. thanks !

pH: 7.5
Nitrate: 0 ppm
Nitrite: 0 ppm
GH: 60 ppm
KH: 40 ppm

betta in 5gal tank

i know the GH is supposed to be between 5-20 but mine is at 60? is that right? im not very sure what GH is really but ill read about it. is there a way to lower it if i need to? i added almond leaves yesterday , i know it lowers the pH but does it also affect the other parameters?

thanks
 

Heron

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GH is a measure of water hardness. That is basically the ammount of dissolved salts in your water, it is similar to KH which is the ammount of buffering salts. GH does not really affect other water parameters like KH does. Some KH is good as it stops pH from dropping. Some GH is good as it provides minerals that plants need to grow. The only real way to lower either is to dilute the hard water with pure water like distilled or RO water. I assume these high readings come from your tap water. You can check this by testing some tap water, but let it settle a couple of hours before testing or you will get weird results. If it's not the tap water then it would likely be from using the wrong substrate. Substrates like limestone , crushed coral or coral sand make the water hard and should only be used in freshwater aquariums where you want hard water conditions. If you are unsure about the substrate or decor put a few drops of vinegar on a piece, if it reacts then it is unsuitable. If your tap water is to blame and you don't want the expence or inconvenience of distilled / RO water I suggest you try keeping fish that prefer hard water.
 
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Blueberrybetta

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pH: 7.5
Nitrate: 0 ppm
Nitrite: 0 ppm
GH: 60 ppm
KH: 40 ppm

betta in 5gal tank

i know the GH is supposed to be between 5-20 but mine is at 60? is that right? im not very sure what GH is really but ill read about it. is there a way to lower it if i need to? i added almond leaves yesterday , i know it lowers the pH but does it also affect the other parameters?

thanks
GH is a measure of water hardness. That is basically the ammount of dissolved salts in your water, it is similar to KH which is the ammount of buffering salts. GH does not really affect other water parameters like KH does. Some KH is good as it stops pH from dropping. Some GH is good as it provides minerals that plants need to grow. The only real way to lower either is to dilute the hard water with pure water like distilled or RO water. I assume these high readings come from your tap water. You can check this by testing some tap water, but let it settle a couple of hours before testing or you will get weird results. If it's not the tap water then it would likely be from using the wrong substrate. Substrates like limestone , crushed coral or coral sand make the water hard and should only be used in freshwater aquariums where you want hard water conditions. If you are unsure about the substrate or decor put a few drops of vinegar on a piece, if it reacts then it is unsuitable. If your tap water is to blame and you don't want the expence or inconvenience of distilled / RO water I suggest you try keeping fish that prefer hard water.
Thank you for the detailed response ! Really helped . I use spring water for his tank , should I switch to distilled water? And the substrate I use is "CaribSea planted aquarium substrate". I don't see any limestone on the back
 

MrBryan723

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Kh is potassium hardness, gh is general hardness or everything else including calcium hardness. Bettas prefer softer water so mostly the gh. You can have a relatively high kh and still have softer water.
 

fjh

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Kh is carbonate hardness and Gh is general hardness.
Kh buffers your Ph - meaning it prevents it from swinging around. Specifically in aquariums, Ph tends to lower between water changes (from the nitrate mostly), but the Kh will absorb it all instead - at least until KH hits zero and then you can expect to see your Ph go crazy.
Gh is the same thing as "hard water" vs "soft water." Calcium and magnesium are the two major minerals that influence this, but there are others.

In all tanks, the most important one of the 3 in Ph - specifically that it does not change wildly. To this end, you want a higher Kh, to prevent the Ph from moving. Gh is completely separate, and a betta does well is basically any Gh you would get out of your tap.
 

Heron

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You could use distilled water but once you get the KH and GH down mix it with some tap water because you want to keep some KH and GH otherwise your pH will become unstable.
 
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Blueberrybetta

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Yes you can use bottled spring water. Test its parameters on its own first to see if it has a lower gh.
i just tested the spring water .

pH: 8.0
nitrite: 0ppm
nitrtate: 0ppm
KH: 240ppm
GH: 180ppm

so all the ppm are high so o you think its the spring water i use? the GH basically had the same dark color as my tank, but i use a conditioner for the spring water. what do you recommend ? should i go back to tap water ? thanks

You could use distilled water but once you get the KH and GH down mix it with some tap water because you want to keep some KH and GH otherwise your pH will become unstable.
so distilled water helps lower the KH and GH? cause mine are high for some reason
 

Salem

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The spring water could be the cause of it, changing to conditioned tap water may help if its gh is lower than that of the tank.
Using distilled water will lower kh and gh if you mix it. Using it on its own to fill a tank is unadvised because it has no minerals and will let your ph swing freely.
 
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Blueberrybetta

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The GH for my betta is at 60ppm. i read that 60ppm is too high and needs to be between 5-20ppm. ive heard to use distilled water to help lower the levels, is this true? I know i need to track the ph, nitrate, nitrite ,and GH but do i have to keep up with KH ?
 

Bryangar

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It’s not needed as most fish will adjust fine to any params. Just don’t use distilled.
 
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Blueberrybetta

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It’s not needed as most fish will adjust fine to any params. Just don’t use distilled.
What about spring water ? I tested the spring water itself and the parameters were higher than recommended for bettas but is it better than tap water ? Not sure what water to use
 
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