# How to lower GH



## MochaLatte (Nov 19, 2011)

Ok a little tank info. It is a 20 long has been up and running for over a year. Has plain gravel with crushed coral mixed in, I used to have small fish in it before finding out I could keep shrimp alive in it. I can't get the crushed coral out of it without tearing the tank down and I don't want to upset the balance I have right now. I use peat granules to lower the PH. I am using mostly Distilled water, but on occasion still use tap water.

Tank readings:
PH 6.6
KH 2
GH 17

Tap readings:
PH 8.8
KH 3
GH 10 

When I do use the tap water I mix it with Distilled water to try and get the PH the same as the tank PH


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## plamski (Sep 25, 2009)

Go with RO or Distilled water only till you get desire levels and then you can add more KH if you need it.


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## jmowbray (Dec 20, 2009)

Ya as plamski said the only real way is with RO/DI water. What ever you do don't use things like the chemical GH-up, down or pH-up, down stuff. They do more harm than good.


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## MochaLatte (Nov 19, 2011)

I never use chemicals in any of my tanks. I can only get distilled water till I get the money to buy a RO/DI system. My parents have an RO system, but I tested the TDS and it's over 50...Will be getting RO/DI hopefully this month though.


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## Wasserpest (Jun 12, 2003)

Me... I would switch out the substrate. It is just a 20gal tank, and you should have plenty plants and established filter media to get all of this done in a day. Re-doing a tank is fun. :icon_mrgr And if you have gotten it into balance now, you will get there again.

Adding just distilled water will drop your kH further, so then you might have to add something like baking soda to raise the buffer capacity, etc etc. Do-able but perhaps wiser to just bite the bullet. Will save money in the long run, less chemistry to worry about and meddle with, and being able to do regular/frequent water changes with just tap water makes things easier.


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## MochaLatte (Nov 19, 2011)

The low KH is why I have crushed coral in the tank. Without the crushed coral my PH plummets below 5. This is why I am hesitant to change the substrate. I've only been keeping shrimp for a few months and don't want to mess up what I got going. Oh and the TDS in my tap is higher than I want in my shrimp tank.


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## Wasserpest (Jun 12, 2003)

Yeah, don't fix what is not broken.

Sounds like a catch 22 though. You want to reduce GH, which is caused by crushed coral, which you added to raise KH. Probably better to look for a way to buffer KH without raising GH.


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