Baking soda and cory's

[cjldad]

I need to buffer up my KH and have put some marble chips in my canister.. However, I need to supplement that for the time being.. My KH out of the tap is 2 degrees.. And my ph over the past week has been coming down... Been doing water changes, but it only helps for about 2 days...

My question is will baking soda hurt my plants or my cory's? Only reason I ask is because of the sodium in the sodium bicarbonate..

I plan on adding it extremely slow over the weekend...
Just making sure.. Thanks!

 

[Lynae]

Baking soda has a very temporary effect on aquariums KH and PH, I learned that when I was first starting out. You add the amount, test the water, and it seems like its perfect, but within an hour or two the water reverts back to whatever KH and Ph it was before. I don't suggest using baking soda!

 

[cjldad]

So, just hope and pray?

 

[jsoong]

You need to use baking soda properly if you want the effect to last. It will give the yo-yo-ing pH effect if you use too little, or if there is a second buffer in the water.

Generally, you need to add baking soda against the KH level. If you titrate the baking soda against pH, you are mush more likely to run into problems. In the OP's case, the KH is low & pH is unstable, so there is not likely to be a 2nd competing buffer. So the only thing to worry about is to add enough to bring the KH up to a level to ensure pH stability.

I would suggest you aim for a KH of 4-5, and let the pH fall where it may, as long as it is stable. <It should be in the low/mid 7's.> To do this you need to add ~1-2 teaspoon per 20 gal. <Do it gradually in steps & verify with your KH kit!.>

The amount of Na added is less than 100 ppm, this is fine for fish or plants.

In the long run, you are better off using CaCO3 (crushed coral, limestone, shells, etc) Because of the low solubility, changes are much more gradual and tends toward equilibrium automatically. Once your tank is stabilized on cc, you should reserve baking soda for when you need to do an emergency large water change & need to match tap to tank in a hurry.

Read this for more detailed info (scroll up & follow the links as well):
Beginner FAQ: Water Chemistry

 

[cjldad]

Yeah, I'm just looking to buffer.. Not looking to adjust Ph, but know it will go up when the Kh is buffered.. My other tank hold around 7.2 to 7.4.. And doesn't have anything other than the fish waste to slowly pull it down.. Big tank has large chunks of driftwood and some plants..

I read the marble chips will help just as the crushed coral, etc would.. Am I mistaken? Thanks for the help!!

 

[jsoong]

marble chips will work just fine. Although if you have big chips, it will take much longer to dissolve compared to cc (which is like 1/4" size).