Navyblue
Low maintenance first
Long story short, I have a need to substantially reduce nitrate. I dosed carbon a while back. I don't remember the dosage I that I used, I don't even remember what kind of I dosed. I also no longer have my tank log. The only thing I remember is it has a dramatic effect on nitrate reduction on my tank then. So I did a search on my past post and found my chronicle, it was dated 2004. 
How time flies. I thought the memory of internet is could be useful at times. So I thought I would chronicle what I am going to do again in case I need it again in the future, it might also serve as anecdotal reference for others. Back then the carbon dosing scene was very different. We get questioned why there is even a need to dose carbon. There was no dosing table to refer to. There was no biopellets.
After researching again, the obvious thing to do seem to dose vinegar and follow the dosing table. Although I didn't really follow it. I understand that it is the very conservative approach. I started at around week 5 on the first week and jumped to week 10 on the following week. I observed no ill effect.
Tank: 120G with sump (net water volume estimated to be around 120G)
Livestock: 1 medium fish (powder blue tang), 5 small fishes (damsels, clownfishes, chromis), 1 banded serpent star
Week 1: 25ml vinegar daily (nitrate estimated at about 500ppm)
Week 2: 50ml vinegar daily (nitrate estimated at about 80ppm after 80%+ water change)
I added 2L of Seachem Denitrate and more macro algaes in the refugium after the water change. I was hoping they would help the liverocks maintain nitrate level after I reduce the nitrate. The liverocks alone obviously wasn't nearly enough that brought me to this in the first place. The only other filtration is the skimmer (H&S 150-F2001 rated for 220G)
At week 3 I increased the vinegar dosage to 75ml. I observed cloudy water, but it is nothing major and it would clear up in half a day. I repeated 75ml and got the same result. I then reduced the dosage to 25ml which was known to be safe at initial dose, still same result. I repeated the 25ml dosage the next day, still same thing. I tried dosing Microbacter7 as I read that it would clear up water, it didn't prevent the cloudy water, but when it cleared up the water became noticeably clearer than before, but that is topic for another day.
After the multiple bacterial blooms, I expected significant nitrate reduction. But when I tested it there is no measurable difference (with hobbyist test kit). I was kind of disappointed. It is not what I remembered it to be. I took a look at the said 10 year old thread and found that I was dosing at a much higher rate without clouding the water. But I was also dosing sugar instead of vinegar.
At first I thought it is a case that every tank is different. After further research, I found that it appears to be the norm. Vinegar dosing takes weeks if not months to have observable effects in very high nitrate tank. Some even report that it doesn't work. Then I found that there are anecdotes of sucrose being more effective in lowering nitrate. I thought, this could be it. That was what I did, I zeroed my nitrate in a matter of days, not weeks or months.
So I hypothesize, at least in my tank, vinegar is boosting bacterial growth to the point of cloudiness, but not the kind that takes up nitrate efficiently. Perhaps it is the case with all tanks too, especially for those that reports vinegar does not work in reducing nitrate. It might work for maintaining low nutrient tank, but from what I read so far it would not have dramatic effects on nitrate like my experience with sucrose. May be vinegar would work if I give it enough time, say months, but I am interested in looking at other carbon source that would reduce nitrate more and cloud my water less.
I will leave it to someone else who have more technical knowledge to speculate how I managed to zero nitrate in matter of days, or if more complex carbon source is indeed superior in lowering nitrate by fuelling a more diverse set of bacteria which would include some that are more efficient at lower nitrate. I will merely chronicle my actions and observations.
The obvious candidate is sucrose as I had good luck in the past. Some reported ill effect on corals or anemone, but I don't have any of those at them moment. While searching for a cheaper carbon source than vinegar, I found that dry citric acid cost less than vinegar in supermarket. It is a tad more complex than acetate, but not as complex as sucrose. I am interested in finding out if it would allow me to lower nitrate faster without clouding the water. At the moment, there are very little examples on people dosing citric acid as carbon source. There is another member chronicling his experience with citric acid recently, but I thought it would be better for me to not hijack the thread.
I will continue dosing Microbacter7 according to the instruction (2 weeks of 25ml per day initial dose, followed by maintenance dose if necessary). I will also stop dosing any carbon source for a couple of days till the system is stabilized. After that I would dose 25ml of 5% citric acid for the fist week and ramp it up by 25ml per week. If the water is still clouding after dosing, I guess I will have to wait even longer.
How time flies. I thought the memory of internet is could be useful at times.
So I thought I would chronicle what I am going to do again in case I need it again in the future, it might also serve as anecdotal reference for others. Back then the carbon dosing scene was very different. We get questioned why there is even a need to dose carbon. There was no dosing table to refer to. There was no biopellets.After researching again, the obvious thing to do seem to dose vinegar and follow the dosing table. Although I didn't really follow it. I understand that it is the very conservative approach. I started at around week 5 on the first week and jumped to week 10 on the following week. I observed no ill effect.
Tank: 120G with sump (net water volume estimated to be around 120G)
Livestock: 1 medium fish (powder blue tang), 5 small fishes (damsels, clownfishes, chromis), 1 banded serpent star
Week 1: 25ml vinegar daily (nitrate estimated at about 500ppm)
Week 2: 50ml vinegar daily (nitrate estimated at about 80ppm after 80%+ water change)
I added 2L of Seachem Denitrate and more macro algaes in the refugium after the water change. I was hoping they would help the liverocks maintain nitrate level after I reduce the nitrate. The liverocks alone obviously wasn't nearly enough that brought me to this in the first place. The only other filtration is the skimmer (H&S 150-F2001 rated for 220G)
At week 3 I increased the vinegar dosage to 75ml. I observed cloudy water, but it is nothing major and it would clear up in half a day. I repeated 75ml and got the same result. I then reduced the dosage to 25ml which was known to be safe at initial dose, still same result. I repeated the 25ml dosage the next day, still same thing. I tried dosing Microbacter7 as I read that it would clear up water, it didn't prevent the cloudy water, but when it cleared up the water became noticeably clearer than before, but that is topic for another day.
After the multiple bacterial blooms, I expected significant nitrate reduction. But when I tested it there is no measurable difference (with hobbyist test kit). I was kind of disappointed. It is not what I remembered it to be. I took a look at the said 10 year old thread and found that I was dosing at a much higher rate without clouding the water. But I was also dosing sugar instead of vinegar.
At first I thought it is a case that every tank is different. After further research, I found that it appears to be the norm. Vinegar dosing takes weeks if not months to have observable effects in very high nitrate tank. Some even report that it doesn't work. Then I found that there are anecdotes of sucrose being more effective in lowering nitrate. I thought, this could be it. That was what I did, I zeroed my nitrate in a matter of days, not weeks or months.
So I hypothesize, at least in my tank, vinegar is boosting bacterial growth to the point of cloudiness, but not the kind that takes up nitrate efficiently. Perhaps it is the case with all tanks too, especially for those that reports vinegar does not work in reducing nitrate. It might work for maintaining low nutrient tank, but from what I read so far it would not have dramatic effects on nitrate like my experience with sucrose. May be vinegar would work if I give it enough time, say months, but I am interested in looking at other carbon source that would reduce nitrate more and cloud my water less.
I will leave it to someone else who have more technical knowledge to speculate how I managed to zero nitrate in matter of days, or if more complex carbon source is indeed superior in lowering nitrate by fuelling a more diverse set of bacteria which would include some that are more efficient at lower nitrate. I will merely chronicle my actions and observations.
The obvious candidate is sucrose as I had good luck in the past. Some reported ill effect on corals or anemone, but I don't have any of those at them moment. While searching for a cheaper carbon source than vinegar, I found that dry citric acid cost less than vinegar in supermarket. It is a tad more complex than acetate, but not as complex as sucrose. I am interested in finding out if it would allow me to lower nitrate faster without clouding the water. At the moment, there are very little examples on people dosing citric acid as carbon source. There is another member chronicling his experience with citric acid recently, but I thought it would be better for me to not hijack the thread.
I will continue dosing Microbacter7 according to the instruction (2 weeks of 25ml per day initial dose, followed by maintenance dose if necessary). I will also stop dosing any carbon source for a couple of days till the system is stabilized. After that I would dose 25ml of 5% citric acid for the fist week and ramp it up by 25ml per week. If the water is still clouding after dosing, I guess I will have to wait even longer.
