Baking soda & Washing soda ? Brad?

[Mutagen]

Fishbait,

This thread is getting long and I'm no longer sure what all your questions are, so I'll try to translate what Mike said into chemical equations.

CO2(g) <-----> CO2(aq) _________H
H2O + CO2(aq) <----> H2CO3 _____Keq1
H2CO3 <-----> H+ + HCO3- _______Keq2
HCO3- <-----> H+ CO3-- _________Keq3
H2O <-----> H+ OH- _____________Keq4

Each of these equilibrium equations has its own equilibrium constant. The solubility of CO2 will depend on the partial pressure of CO2 in the surrounding atmosphere and it has its Henry's law constant. At equilibrium, all the equation's equilibrium constants are satisfied. Anything which perturbs the system will temporarily create a state of disequilibrium. For a given alkalinity and CO2 partial pressure there will be only one equilibrium pH. However, our systems are in a constant state of change with respect to both alkalinity and dissolved CO2. We also perturb the system when replenishing alkalinity and calcium. The manner in which the system is perturbed depends on the method we choose to replace the alkalinity.

The equilibrium constants for these equations in salt water systems are now fairly well established and it is possible to solve for all the constituent concentrations at equilibrium. Basically it is 5 equations and 6 unknowns plus a charge neutrality requirement so the system is properly specified for a unique solution.

This system provides a great deal of confusion. It is a simultaneous equilibrium system where CO2 effects pH but not alkalinity. Furthermore, we use the terms alaklinity and buffer interchangeably though they don't have the same chemical meaning, but that's OK becuase the alkalinity and buffer capacity are provided by basically the same constituents!

If you continue to pursue chemistry courses, you will eventually study multi-component, multi-phase equilibrium and all will be revealed!

Good luck, Mutagen

[Aaron Shelley]

Went to Walmart and United (the largest supermarket chain in West Texas). Couldn't find Washing Soda. Had the clerks look it up on the computer (since they had never heard of it) and it wasn't there.

Where do you folks buy it at?

If I can't find it, I'll give Mutagen's baking the baking soda thing a go. How precise is the 450 deg for 30 minutes thing?

Sound like a fun and an easy DIYer and I'll save a buck or two. That's 20 minutes of long distance you know!!

[Doug]

Hi Aaron,

My wife picked up my Arm and Hammer washing soda at Jewel. I am not sure if they have stores all over the Country but it is a large food store chain in the Chicagoland area.

Did you look in the detergent section? My wife said it was near the dish soaps and household cleaning solutions.

HTH

Doug

[Aaron Shelley]

thanks doug

that's where i looked too.

[MIKE]

Hi Aaron,

I found it in the local grocery store, Save Mart. When I mentioned to my wife, she knew about it instantly (I'd never heard of the stuff). I would try some other local grocery chains, but you probably already know that

[MIKE]

Hi Aaron,

I had another thought. Like I mentioned earlier in the thread, you can also find sodium carbonate at pool/spa supply places, or hardware stores where they sell ph products for pools. Just check the label because various chemicals are used for ph up products. But some definately use sodium carbonate.

Another possibility is to send me an email with your address and I'll buy you a coupla boxes of washing soda and send it to you. This amount will only last you .... like about 5 yrs . I'd gladly do that if you want.

[Aaron Shelley]

Thanks Mike!!

Let me give it "the old college try" today. I've got three more stores mapped out. One of them was the LFS. If I couldn't find it at the first two, I was going to throw in the towel and buy buffer at the LFS

I'll email you if I'm unsucessful.

Thanks again. Yet another reason why this board is so good. It is full of good people...

[scorpio241]

Is it 1 part baking soda to 6 parts washing soda or 6 baking soda to 1 washing soda

[chriss]

Originally posted by Doug
I had added some Tropic Marin Bio-Calcium last night and will continue to use that and the combination of Brad's buffer to bring things back to par. Doug

Doug,
I just wanted to point out that Tropic Marin Bio-Calcium increases alk. If you want to just increase ca, use calcium chloride instead. I know it doesn't state this on the container (I use it also), but according to my test kits and RFH it is a balanced additive.

Chris

[Doug]

To Reef Central

Originally posted by scorpio241
Is it 1 part baking soda to 6 parts washing soda or 6 baking soda to 1 washing soda

The correct formula is 6 parts baking soda to one part washing soda.

Here is a simple webpage that I created a while back that might be of some help.

http://www.hawkfish.org/infoctr/homebuffer.htm

[Doug]

Originally posted by chriss
Doug,
I just wanted to point out that Tropic Marin Bio-Calcium increases alk. If you want to just increase ca, use calcium chloride instead. I know it doesn't state this on the container (I use it also), but according to my test kits and RFH it is a balanced additive.

Chris

Thanks Chris.

I didn't know that about the Bio-Calcium and appreciate the info.

I ended up installing a Calcium reactor on my 90g tank since the calcium load in my tank kept increasing with the addition of more SPS corals.

Thanks again.

[scorpio241]

Originally posted by Doug

To Reef Central



The correct formula is 6 parts baking soda to one part washing soda.

Here is a simple webpage that I created a while back that might be of some help.

http://www.hawkfish.org/infoctr/homebuffer.htm

Great thanks so much

[JEMichael IV]

Probably a stupid question but when you say 6 parts to 1 part is that a certain amount or can it be 6 cups to 1 cup or 6 oz to 1 oz?

Just verifying. Thanks

[Frick-n-Frags]

Use whatever measuring units you wish, just keep the ratio 6:1.

So 6 cups to 1 cup or 6 grams to 1 gram all works.

This needs some more confusion
I found that I was having chronic high pH issues because I dose kalk which has much higher pH than even washing soda, so I had to eliminate the washing soda from my buffer formula.

The pH of baking soda seems to want to be about 8.0 which chills out the kalk. (7.0 is neutral, so it still fizzes vinegar at pH 8.0. Our tanks are somewhat basic) Now my pH hangs around the 8.1-8.3 range very nicely. It still goes up a little during the day, but I have a ton of algae making a ton of oxygen, so it makes sense.

[JEMichael IV]

Yes thanks Frick-n-Frags! I mixed it up and dosed according to the teaspoon per 25 gallons on the website for the first time 2 1/2 hours ago. I did a test and it did bring my alk up 1.2 dkh. I want to dose again to bring it up some more, but how long should I wait or does it matter? PH is stable at 8.33 currently.

ALK was at 7.8 and now is at 9. I would like to get it to 10-11 but dont know how long I should wait between dosing or if it even matters.

Thanks
John

[Bomber]

This may be a silly question but why are you guys running all over God's creation trying to get washing soda when you can just bake baking soda in the oven and you get washing soda?

[Mutagen]

Wow, somebody really dredged deep for this old thread.

Bomber, I neglected to mention this way back when but its even EASIER than baking the stuff. All you need to do is mix the baking soda in (Tap or DI) water in a glass and let it sit for a couple of hours. The pH will rise all by itself. If you're impatient, just nuke it in the micro-wave for 30-40 seconds. I continue to be amazed at how many people still buy the "prepared buffer formulations".

Mutagen

[JEMichael IV]

Hey Mutagen do you think you can give me any suggestions on how long I should wait till I buffer the tank again? Are there any limitations besides watching the ph, alk and cal levels?

[Mutagen]

Hi JEMicheal,

I'm not entirely sure I understand the reason for your question. Adding buffer is generally an ongoing job and one should consider buffer and alkalinity synonymous. Add at a rate that it is depleted as measured by your alkalinity test kit. But you already knew that, so maybe you are thinking of something else?

Mutagen

[JEMichael IV]

Hi Mutagen, what I ment was I just doesed my tank and tested it a few hours later and it did increase. I didnt know if I could buffer it again then or if I should wait 24 hours till the next buffer. For example BIONIC states to buffer every 24 hours. That is what I ment.

[Russel]

what a great thread! can't wait to share this with some freinds!

[JeffDubya]

This is an excellent thread. An excellent thread that makes 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. Please, no open mocking. Mocking via PM is allowed provided I am not included in the discussion.

OK, so my first question has to do this homebrew pH 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.) 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.

(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?

Eventually I will get all of this. And maybe write the “Water Chemistry for Dummies� text. Maybe.

[DaveG99]

great info here !!!