Yet another TM All For Reef question thread with some specifics about organic chemistry

[rennjidk]

A little to wordy and too many questions to place in the title

1. Is there an initial "cycle period" in which methanogens need to populate in order to process the formate in AFR or other organic carbon sources (assuming we are starting with a newly nitrogen cycled tank)?
2. If one is "yes", are there any additives which can boost the population during this period, or will they naturally form with the addition of frags from established tanks?
3. Regarding oxygen depletion, is there a correct time to dose AFR, and would the tank benefit from spreading that dose throughout the day?
4. I was able to detect a significant change in dKH using an API test kit immediately after dosing AFR (with multiple tests both before and after). How is this possible with formate needing to break down in order to be detectible? Is there something specific to API that could interact with the formate in this product? (I use a Hanna Checker for actual tests, I just thought it was interesting enough to include).
5. My corals have seemed to react negatively to AFR in my established tank. This is anecdotal at best, but again worth mentioning. After starting dosing AFR, I had 2 fist sized Goni's exhibit rapid tissue necrosis within 4 days (they now have "bowl cuts"). After checking my parameters daily, nothing had dramatically changed during this period and I had no other changes in routine. I don't understand what could have caused them to immediately die off by half in a system that still tests for the same Ph, dKH, Cal, Mag, ect.

 

[blaxsun]

Don’t take this the wrong way, but anything tested with an API is a little suspect.

 

[Spare time]

For 2, they (tropic marin) recommend dosing afr during the day. I wouldn't be too concerned. I dose about 100ml a day in my tank, sometimes at night.

As for 5, I doubt they were related at all. Remember, correlation does not equal causation.

 

[Dorsetsteve]

I can’t authoritatively answer your questions but I’ve been using AFR for quite some time now. In honesty I think you may be over thinking it.

I dose it on the hour, so 24 doses per day. To my mind with the way it becomes available as carbonate it’s a slower or less reactive addition than say Bicarbonate. So in reality it’s probably not all that important, especially if your not approaching the max dose. Any corrective dose I base over at least 48 hours.

With AFR you are dosing Magnesium as well as a roll call of traces. So whilst it’s unlikely, you may find additional testing reveals that one of those will be elevated. Unless you are testing for these you wouldn’t know…You may be aware or not, that there is another product CarboCalcium which is AFR without the trace and Mag, perhaps this may be better suited?

 

[Randy Holmes-Farley]

I think there may be many bacterial species that can take up and metabolize formate, and that it may happen fairly rapidly in a reef tank:

https://www.mdpi.com/2076-2607/8/3/454/htm

Also, while most of it will not show up in an alk titration, some formate will be detected by an alk titration. It’s pKa (3.75 in fresh water) is not far below the CO2 titration endpoint of about pH 4.3. Thus some fraction of formate ions will be detectable as total alkalinity (but much less than half of it, maybe 10-20%.

 

[rennjidk]

I think there may be many bacterial species that can take up and metabolize formate, and that it may happen fairly rapidly in a reef tank:

https://www.mdpi.com/2076-2607/8/3/454/htm

Also, while most of it will not show up in an alk titration, some formate will be detected by an alk titration. It’s pKa (3.75 in fresh water) is not far below the CO2 titration endpoint of about pH 4.3. Thus some fraction of formate ions will be detectable as total alkalinity (but much less than half of it, maybe 10-20%.

This is exactly what I was looking for and could not for the life of me find any resources on it. Thank you.