Homebrew pH Buffer... and more

JeffDubya · 10-10-2007, 03:08 PM

Last night I read a huge thread about “homebrew pH buffer” on one of the bigger web forums. It really was an excellent thread. An excellent thread that made me feel like a complete moron. I'm terrible with chemistry, I don't understand this stuff as well as I should, but here's the deal: I have low pH and I would really like to fix it!

So here are the stupid idiot questions.

OK, so my first question has to do this buffer. If it's this easy, then I am never buying it again. I really love supporting SeaChem, but not if I don't have to. I have a few questions specifically related to that.

(1.) The recipe calls for “Washing soda.” Nope, can't get it here. Tried 3 hardware stores and 4 grocery stores. Every customer service person I recruited for assistance... and my WIFE... looked at me like I was from another planet. So, I'm now thinking about another source for sodium bicarbonate. Someone mentioned earlier that pool and spa chemicals were sodium carbonate, and they sure were correct. 97% sodium carbonate and 3% of who knows what. Has anyone else used pool and spa chemicals in their VERY EXPENSIVE INVESTMENT OF A REEF TANK before? The thought kinda freaks me out, as illustrated by my obnoxious use of all caps. Is this doable?

(2.) If sodium carbonate raises pH, and sodium bicarbonate (baking soda) lowers pH, why are we using both? or when we say “buffer” pH, are we not really talking about “raising” it? The pH of my water is notoriously low. I don’t know why. With my hot tub, I ALWAYS have to add sodium carbonate when I add new water. With my fish tanks, my other parameters are practically perfect, but the pH is low. I am always around 7.9 to 8.1 and I want to get it up to around 8.3. If all I am doing is trying to RAISE my pH, can I use sodium carbonate by itself? AND will the stuff I have for my spa work without nuking my livestock?

(3.) I am adding a calcium reactor. Will all of this discussion be a moot point?

Thanks for reading - and hopefully educating me.

**CarmieJo** · 10-10-2007, 11:03 PM

Buffer is a solution's resistance to change in pH, not a specific pH. pH, Ca and alk are all tied together. Have you tested them? Have you tried aerating a cup of water with outside air for an hour and retesting? It may be that there is too much CO2 in the indoor air and that is lowering pH.

Sodium bicarbonate has a pH of a little over 8, sodium carbonate's is higher about 11.

Calcium reactors LOWER the ph.

JeffDubya · 10-12-2007, 03:22 AM

So Carmie, without getting the physics lesson I would love to have you give me, if I just want to bump up my pH, would the spa chemcals be a bad idea, as long as they are dissolved in solution and dripped in a little at a time?

I am at about 8.0 now. I want to be at 8.3 - 8.4

Mr. Tang · 10-12-2007, 07:56 PM

Well lets talk about the homebrew recipe you found. I'm assuming you're talking about RFH two part system. Is this correct??? If so, continue reading. If not than read anyways!!!!

If you're using this and your ph is still low, Than you should look at version 2. It has stronger mixes in it for low ph tanks.

Something else to think about is this. If you could drip Kalkwasser(limewater) you could keep your ph stable. Limewater has a high ph and if dripping properly, you could keep your ph up by adjusting the drip amount.

Mr. Tang

**CarmieJo** · 10-12-2007, 11:30 PM

Here is the article An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com about a homemade 2 part solution. In this article recipe 1 is for tanks with normal to low pH. I agree that dripping kalk would raise your pH but it is only used if both Ca and alk are already balanced and in range. Otherwise you need to use a 2 part solution.