Buffering capacity.

[Mannie]

Ok I have a question for all you guys that know. I set up my tank yesterday. It has 31 pounds of live rock 21 pounds of base rock 20 pounds of live sand and 30 pounds on reef sand. I did all my test as I was told to. All the test seem to be coming out good except for my buffering capacity. Can someone explain to me what this does? I was reading somewhere that it kept the PH stable but I am not sure if it should be unreadable. that means that the color it is turning ain't even on my test strip chart. I used RO water that was premixed with salt. The hydrometer is reading 1.024. Thanks.

[drummereef]

Arm & Hammer Baking Soda will bring up your Alkalinity. Target 7-11dkh or 2.5-4meq/L. Use the calculator below to help in dosing. ;)

Reef chemicals calculator
http://home.comcast.net/~jdieck1/chem_calc3.html

You should probably pick up a titrate-style test kit for testing Alkalinity. Salifert, AP, La Motte are all good.

In the future, you might want to get on a balanced additive as it's hard to keep the alkalinity, calcium, and magnesium in balance using seperate additives.

How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

Also, it is acceptable for your salinity to be 1.026. Bringing that up will also introduce more buffer from the salt mix.

[Mannie]

Thanks, but I am not sure that those sites answer my question. On my test it's turning blue but it doesn't have a blue on the chart. So how do I know if it's too high or low? I would hate to add something and it not need to be added.

[kevin2000]

PH is just a measurement of Hydrogen Ions.

A simple way of thinking about buffers is that they act as a reservoir for hydrogen ions .. giving and taking them in order to maintain a reasonable level of PH.

The two primary "buffers" in our systems are bicarbonate and carbonates ... one keeps the PH from rising the other from falling. They basically toss the Hydrogen ions back and forth between each other to keep your PH reasonably stable.

Live rock and Live Sand are usually made of calcium carbonate ... the carbonate component is considered a buffer but only comes into play when its dissolved ... many would argue that this process is so slow that it does not have a meaningful impact on your tank.

[Mannie]

Thanks Kevin. So what I am getting from that and everything I have read about it. Is that as long as it doesn' drop to low it is ok? That way the PH will remain stable. Right now my ph is 8.4 i believe.

[kevin2000]

In general so long as you have adequate alkalinity combined with reasonable aeration (little surface water turbulence is fine) then PH tends to be fine. PH will naturally rise throughout the day when the lights are on and then fall when the lights are off .. this is due in large part to the presence of algae which generate oxygen when the lights are on (photosynthesis) and CO2 when the lights are off .. that CO2 creates a mild acid which depresses PH.

Its common for PH to fall below 8.0 at night and exceed 8.2 late in the day.

[Boomer]

that means that the color it is turning ain't even on my test strip chart.

What are you talking about here. The pH where you are using a test strip or the buffering capacity with a test strip. They are not the same thing. And are you saying test strips or a test kit. Test strips are not very reliable. What exactly are you testing with. They may not be able to work well in seawater.

It sounds like it is a pH test strip and blue usually indicates pH in the 8's with this method