This week I tested Ecological Labs Microbe-Lift 7.5 pH Buffer Stabilizer to determine if it would stabilize my pH at 7.5. It did not. My pond continues to fall below 7.5 at both morning and night. The goal is to keep my ph at 7.5 or above so that nitrifying bacteria can reduce my nitrites. This product may work in some ponds but not in mine.
I have 1600 gallons with 8 medium koi. Water changes 15-20% per week.
Added 2 lbs per instructions.
pH rose above 7.5 initially and has fallen as low as 7.2 1 week later.
This would be my normal pond behavior so buffering has no effect.
Only other chemical used was Chlorine remover when adding water from mains.
Only 1 filter cleaning performed during this time.
I would call this product a failure. If you have had luck with this product please let me know your particulars.
First, I’d like to correct some technical errors. [NOTE: In original posts above I have made some of the suggested changes to technical errors. ]
Nitrifying bacteria do not remove, or reduce nitrates. Nitrifying bacteria oxidize ammonia to nitrate and nitrate in a two step pathway. Denitrification is the reduction of nitrate to nitrogen gas, and an excellent way of removing nitrogen from your pond. (For people who have trouble denitrifying, there is an excellent denitrifier in MICROBE-LIFT PL.)
Since nitrification is an oxidative process, it has to occur in an environment with an adequate supply of dissolved oxygen (D.O.). Denitrification is a facultative, anaerobic process where the nitrate, an oxygen bearing inorganic compound, acts as what is called the terminal electron acceptor, and is reduced to nitrogen gas. This will only occur in an environment without D. O. You may ask how you can denitrify in a pond where you must have dissolved oxygen for the fish to survive. Well, there are anoxic zones in the biofilms in you filter and on fixed surfaces in your pond that allow for this denitrification reaction to proceed.
Next, pH is given in a number from the pH scale which goes from 1 – 14. It is not given in %. For those interested in where the 1 – 14 comes from it has to do with the dissociation constant for water. [Original post corrected]
Now, to get to the performance of the 7.5 buffer. Any chemical product, or biological product for that matter, will function a little differently in every pond since pond chemistry varies from pond to pond. You may have a very soft water that has little natural buffering capacity (alkalinity) so would require more than the normally recommended application rate of 7.5 buffer to maintain your pH above 7.5. Nitrification will proceed at an almost optimum rate in a pH range from 7.2 to 8.2, providing there are no inhibitory compounds in the water, so if you are a little below 7.5 it will not hurt nitrification. However, since there seemed to be some confusion, I am not sure you meant nitrification, or denitrification, although you said nitrate reduction, which is denitrification. [Original post Nitrate corrected to Nitrite, which is what I meant to say.]
Finally, active nitrification will lower the pH as ammonia is converted to nitrate and goes into solution as nitrous acid. Like all acids, this will lower the pH. As long as you have fish producing ammonia that is being converted to nitrate, you will continue to need something to buffer the acid, until the nitrate is removed through denitrification.
We have had thousands of customers report very good results with the 7.5 buffer, but, as I said earlier, it doesn’t work the same way in every pond. If you’d like, we can test a sample of your water in our laboratory, and make specific recommendations so that you can get satisfactory results in your pond. If not, we will be happy to reimburse the price paid for the product.
Mark J. Krupka
VP/Technical Director
Ecological Laboratories, Inc.
While I appreciate your offer to test my water, I am quite familiar with its low alkalinity. What I am trying to do is stablize my pH at 7.5 ish so that the bacteria that perform the Nitrite to Nitrate conversion can thrive. My plants usually do a good job of “eating” the Nitrate and I am less concerned with Nitrate than Nitrite. I have had success with your products which is why I was so disappointed in this one.
Perhaps you should expand your products instructions to inform users that an additional dosage (cost) may be required above recommended amount if certain parameters are present (ie high fish load, low alkalinity, frequent water changes, heavy rains). At what dosage/conditions does your product work best, becomes harmful, is ineffective, etc. I also might also be more willing to dump more in IF you would disclose what is in it.
All I can find is this on your website:
1 lb. (PHBUF1) Treats over 800 gals. [but per your statement may require more. Words “over 800 gallons” is subject to interpretaion 801 – 899 or is it only 500 in some cases.]
Safely BUFFERS pH Levels & Prevents Wide pH Swings
Includes 2 pH buffers for gentle effectiveness and 3 electrolytes to help maintain osmotic balance
Provides necessary alkalinity for nitrification
Specially formulated to control fish toxicity which may arise from overdosing
Not harmful to fish or plants
I notice there is no claim that it will stabilize the pH near 7.5 even though the labeling on the package is 7.5 pH Buffer Stabilizer
So perhaps I had unrealistic expectations.
UPDATE: pH hit 7.0 this morning. So I’m back to reducing feed, slowly adding baking soda, and on the hunt for oyster shells.