What does a KH + pH Buffer for your saltwater tank do?

Question

I have no idea what this does? How often do you need to use it?

Answer 1

pH buffer just neutralizes the pH levels in your tank. so when you do you water test kit's and your pH is too high, just add some buffer =]

Answer 2

KH measures the carbonate hardness in your water, which gives you a general idea of the buffering capability of the water (which relates to your pH scale). A low KH means you water has little buffering capability, which means that your tank is subject to pH fluctuations.

As your biofilter converts ammonia to nitrAte, it releases acids and uses up bicarbonates (KH = primarily bicarbonates). This results in pH falling over time. How fast this happens depends on the bioload in your tank, how well buffered you source water is and your water change schedule. If pH crashes (gets too acidic too fast, it can kill your biofilter bacteria and your fish.

KH can actually be buffered with baking soda. (recognize the 'bicarbonates'?). It's way less expensive than a commercial product. One thing though: I am not sure that it's ok to use in a saltwater setup since I don't deal with our SW tank. You'll have to check on a saltwater board.

You do NOT need a KH buffer unless your KH is low. Do you have a KH test? That will tell you how hard or soft your water is. Good luck.

Edit: as a general rule, it is best NOT to tinker with pH buffers as that results in constant pH fluctuations which screws with fish gills & osmoregulation. Find what pH your water sits at after bubbling/sitting out for a day and find what fish best suit that pH. OR use a long-term solution, such as crushed coral substrate to maintain a higher pH.