How to Lower kH?

[mikesbales]

Ok, i'm relativly new to this hobby (about 6 months.) I tested my water this morning because my new starfish died. My kH is at +-20! all my fish are acting fine, but it has to come down! How do I go about doing this? Thanks

 

[Randy Holmes-Farley]

Do you know how it got high?

Adding buffers?

Usually the best option is to let it fall on its own while not adding any. Water changes can work, but take a lot to get a small drop.

Adding a mineral acid is a last resort that I don't generally recommend.

This has more:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

 

[mikesbales]

Yeah I didnt mark on my calendar when I buffered, and I did it twice within the same week. I usually keep it around 10 or 11

 

[Randy Holmes-Farley]

It would be good to know exactly how high it was and to see if it is coming down (20 dKH is different than 50 dKH, for example).

But if you are only adding it once a week, it is probably a low usage tank, and it may take quite a while to come down on its own. That might mean that water changes are the best option.

 

[mikesbales]

I usually keep it around 10 give or take. and I did a 10% water change about 2 hrs. ago, and now somehow its at 22! I dont know what could be effecting it?

 

[HighlandReefer]

What kind of test kit are you using and how old is it?

 

[Randy Holmes-Farley]

A 10% change won't drop it much. Did you measure alkalinity in that new salt water?

 

[mikesbales]

Its an API test kit, and its only about a month or 6 weeks old. The alkalinity of the new saltwater was 9. How frequently can I do a 10% water change?

 

[Randy Holmes-Farley]

Maybe larger than 10% changes? You can certainly do 10% changes each day for a few days.