Adjusting Hardness - The Planted Tank Forum
LinkBack Thread Tools Display Modes
post #1 of 2 (permalink) Old 09-26-2016, 02:31 AM Thread Starter
Planted Member
PTrader: (0/0%)
Join Date: Mar 2015
Location: United States
Posts: 214
Adjusting Hardness

It appears that my GH is a smidge high and my KH is a smidge low. In using the API test kit, it took 2 drops to change color for KH (so 2 dKH, right?) and 8 drops for GH, which the chart says is equivalent to 143 ppm.

I have plants, angels, and tetras (as well as cories, pictus, ropefish, rams, and a betta and gouramis), so it says I need 3 - 6 (50 - 100ppm). I'm off on both. What would be a good way to get my hardness where I need it?

If I'm reading things wrong, please correct me. This is the first time I've ever used a hardness test kit.

Also, my pH is low. I'd fixed that and had it perfect by adding a bag of coral in my HOB, but I removed the HOB in favor of a few sponge filters. I added dragon stone, but apparently not nearly enough? How much stone would I need? Are there other pH raising options that aren't chemicals and don't require HOB/bulky filters?
FuzzyCrawdad is offline  
Sponsored Links
post #2 of 2 (permalink) Old 09-26-2016, 03:22 AM
Planted Tank Guru
PTrader: (84/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 21,012
A KH of 2 degrees dKH is good. Many, if not most plants do very well with that KH. A GH of 8 dGH is also good. It is far better to live with whatever your tap water gives you than to always have to adjust the parameters of the change water when you do water changes. Adding coral to your filter probably raised the KH and GH a little bit, but not much, because as it raises the pH the coral quits dissolving in the water.

If you use rocks that are limestone or dolomite they will always be very slowly raising both the GH and KH, so your water will never be completely stable. Water changes will help keep it more stable, but why introduce that problem when there is no reason to? If you just like the rocks you are using, that is ok too, but then you should do 50% water changes weekly to keep the water more stable in hardness.

KH, GH and pH are not critical parameters except for a few fish and a few plants. For almost all fish and plants, whatever your tap water is is probably just fine for them. If you bought your fish/plants at a local store they were almost certainly just using tap water in their tanks, so the fish are acclimated to that water already.

An exception would be trying to breed your fish. Then, it works best to try to get the parameters closer to what is ideal for each species. But, lots of our fish just breed in our tanks, whether we give them permission or not.

Hoppy is offline  


Quick Reply

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome