What does buffer do. Does anyone use it?
Well I have heard of 2 different things called buffer. One is a true buffer, and it simply adjusts your pH to a certian value. I have also heard Carbonate called buffer. This is because it also adjusts your pH, while adding essential nutrients. Carbonate is used in a 1:1 ratio with Calcium when calcification occours in corals or in calcareous algae. In fact, Carbonate Hardness, or dKH is commonly used to measure a tank’s “Buffering Capacity”. A hardness of 10-12 is good because it not only prevents your pH from swinging as rapidly, but it also promotes good calcification in corals and has many health benefits for fish. I have seen Snook, a saltwater species, which live in a completly freshwater lake down here. How? The dKH is about 25.
I guess the question is which type of buffer are you referring to?
I will have to look when i get home… I will let you know… How is the dkh that high?
The dKH is naturally that high in the lakes because of the geological formations around them. The lakes are spring fed from limestone bedrock, and in freshwater that has a low Ca concontration, the Carbonate doesn’t percipitate out as easily, so the dKH has slowly raised to those levels over thousands of years.
Wouldnt those levels be bad for any inhabitants or plants in the water?
For some it would be, because it is an extreme case. In general though, a dKH on the higher end (12ish) in a saltwater tank can only have benefits to your inahbitants.
FWIW, our 20L mixed reef uses about 1/4 Tsb of Baking Soda a day. Baking soda is one of the cheapest buffers out there. I wasnt much of a beliver in testing dKH before. I just payed attention to pH, Ca, and Mag. Everything did OK…
When I first tested our tank the dKH was approximatley 6. I slowly raised it to 11-12 over the course of a week with normal maintnance, and the difference in polyp extention, color and overall health was AMAZING.
Really, i will have to try this stuff out, gives me something new to do on my tank…
I would reccomend testing with a good quaility test kit before dosing anything. As good as a higher dKH is, if you get it to high it will combine with calcium and percipatate out, dropping your Ca and your dKH. This is one of the problems people have with Kalk… they dose it to fast and it turns to a white soup in their tank because of the percipitation of CaCO3. If you keep it around 12 though you should have no problems.
i have a salifert test, and right now it averages at 8ish
Yeah, I would definatley raise it to 12ish. Most hard corals will live at 8, but wont really thrive untill it is over 10. Remember, for each Ion of Calcium used, they use one ion of carbonate to make their skeleton (CaCO3 - Ca: Calcium, CO3: Carbonate) so any corals you have with a skeleton will also have an easier time lying down new skeleton. Not really any problems with raising the dKH. Like everything though, do it slowly over a little time (week).
How would i go about doing it
Go here: http://home.comcast.net/~jdieck1/chemcalc.html
Then enter your tank size, your current alk, and your desired alk. Once those numbers are in, you can select the type of buffer you are using. I use baking soda, becuase it is cheap and easy. You can also bake the baking soda to make Sodium Carbonate Anhydride, which dissolves a little easier in water, but that takes time and I’m kinda lazy.
All I do is mix up a 1/2 teaspoon with some RO water every other day and dose it (on a heavily stocked 20L). I don’t dose it all at once, as it has a temporary effect of lowering your pH, which is also why you don’t want to do a lot at once. I pour some in, wait 10-15 min, pour more in, wait another 10-15 and pour the last in. If you raise your dKH 1/2 each day it should be fairly safe.
Gordonious & addicted: Sodium BIcarbonate has a lowering effect on reef tanks Sodium CARBONATE will raise your ph of the reef tank I’d recommend dosing 25% or less of what it would take to raise your dKH 1ppm then wait before dosing more as Bellamy says above. I usually leave the jug of water on top of my hood and pour more in later in the day.
Natural sea water’s alkalinity is around 2.8 meq/l or 7 dkh, they can, will, and do thrive under 8 DKH.
The only reason anyone ever suggests you have higher than natural DKH is because it can be hard to maintain alkalinity in a reef tank and while slightly higher levels wont hurt the corals, lower levels will, ergo keep it at 9 DKH so if you slip a point your not killing or stunting your corals. Honestly i would not go higher than 11 DKH and normally am happy if its at 8-9.
Here is an article that could help you out on this.
http://www.advancedaquarist.com/issues/nov2002/chem.htm
edit, having way high alkalinity without balancing calcium to match will cause the excess carbonate to precipitate out so if you want to maintain 12 dkh you would have to try to maintain calcium over 500 and thats just too high.
and corrected salinity to alkalinity… mistype
I have always maintained my tanks at between 8-9 dkh and both the clams and hard corals do great. I have heard of tanks running just fine at 12 and also at 7. I think stability and keeping the correct calcium/alkalinity balance are more important than the actually number as long as it is within the acceptable range.
I agree, stability is the key and the elevated levels are just an “oh crap” measure.
If you can keep it at 2.8 meq/l constantly thats just fine as well.
My personal cap is 4 meq/L or 11 DKH
If you will notice on that link I posted, it gives a balanced Ca or dKH level for the other parameter that you put in. If you run your tank at say… 450, the ideal balanced dKH is about 12.5 dKH. Tanks can definatley be run at a lower dKH. What I am saying is that I see more benefits to running it higher than lower. I tend to run my calcium on the higher end… averaging about 450ppm. So for me the ideal dKH is 12.5 because it provides a balanced level of Ca and CO3, which allows for easier calcification. If someone was to run their Ca level at 415-425, then the ideal balanced dKH is indeed 8 or 9.
People dont realize that they dont do any good by raising one parameter over balance with the other. If you keep both Ca and CO3 at high levels, it allows for faster calcification because the ions are more readily accessible to the corals. Having a calcium level of 550 and a dKH of 7-8 is no better than having a calcium level of 400 and a dKH of 7-8. Your corals wont really grow any faster if one of the ions is held constant and one is raised. When both are raised to a near saturation level, it takes much less for the corals to pull it out of the water, and therefore grow faster. I will say that I do walk a fine line between near saturation and saturation. But as long as you dont cross that line, your corals will grow faster and will be healthier.
FYI this is completely based on opinion. This works for me. I was recommending that Marchingband raise his Alk based on a previous statement that he ran his Ca very high. By raising his Alk, I feel as though he could see a great improvement in his corals by slowly raising his dKH and bringing the Ca into a balanced level.
well, i think im going to try it out… I have some seachem buffer around somewhere…
I made a slight correction in one of Bellamy’s posts above. Correct me if I’m wrong but I believe both Sodium Carbonate or Sodium Bicarbonate will significantly raise the pH temporarily when added.
I also usually strongly urge people playing with chemicals and learning balances and what is going on chemically to use a pH meter. Chemical reagent test kits will cost you more in the long run in my experience and give you horribly inconsistent and inaccurate results. Just keep in mind regular recalibration of the pH probe based on the manufactures recommendations. I’ve heard it said to not allow to raise the pH in the area you add the Sodium Carbonate by more than .2 at a time. Try doing that with a reagent test kit.
sodium BIcarbonate has a lowering effect on reef tanks
sodium CARBONATE will raise your ph of the reef tank
bicarbonate is reccomended to people who dose kalk or have a normally high ph. I believe the max ph bicarbonate can attain is 7.8
both will raise the ph if ur ph is 7.0 tho