CO2, PH, Water Clarity - Vodka, the good, the bad, the ugly!

[Treefer32]

I've been dosing vodka for over a year to manage nitrates with minimal water changes. Nitrates fluctuated between 45 and 65 for most of the year. Then there was a turning point, where I stopped messing with dosing amounts. I settled in at 45 ml per day divided into around 5 times per daytime. I tested nitrates weekly. And gradually they fell. It took it 6 months to get them from 65 at their peak, to 45.
I dosed as high as 70 ml of vodka per day. This clogged up my powerheads with bacterial slime within days. I'd clean them thoroughly and they'd be bound up in bacteria again. I reduced my dosing and this went away!

What worked? - I went from feeding my home made food (which had a lot of benepets coral food and a bottle of selcon in it and some pellets as well). This was raising my nitrates day to day week. I replaced my feeding 6 days a week with feeding the cubed mysis and cubed krill. Within 1 week my nitrates dropped from 65 to 45. I kept my vodka dosing at 45 ml per day.

I continued with this feeding regimen. Feeding 7-10 cubes of mysis / krill (combined total) per day. Substituting that with my food 1 day a week and 45 ml of vodka. Nitrates stalled out around 37 for 3 weeks this past winter. Rather than raising vodka dosing. I decided to do a 40-50% water change. Around 130-140 gallons.

I tested prior and post water change waited a few hours for old and new aquarium water to mix thoroughly).

The pre water change test was approximately: 37.5.
Post water change test: 20.5.

Last week, my doser ran out of vodka, I decided to let it run out and stop dosing vodka all together. I've got a pellet reactor and a full gallon or more of matrix rock and enough Aqua Char to treat 500 gallons of water for 6 months, then it becomes more of a home for bacteria.

That all said, now, stopping vodka dosing and a little over a week of no dosing, my nitrates tested at 20.5 again. Except, now my water is getting clearer by the day. Also, my PH would rarely go above 7.85. while I was dosing.

Results now of not dosing:

• Water clearity is improving by the day. No more floating particles constantly.
• PH Is improving by the day. Yesterday I hit 8.0! Max was consistently 7.7 -7.8 while dosing. Would reach down to 7.5 at night.
• Nitrates remaining stable at 20.5.
• There must be a threshhold where vodka dosing does not do anything as high dosing amounts led to clumps of bacteria in the water column that would get stuck on pumps and powerheads reducing flow, reducing oxygen exchange and there was little to no decrease in nitrates as a reusult of the clumps of bacteria.
• Elminating vodka dosing has not caused substantial increases in nitrates over an 8 day period. (I don't know why this is).

I'm going to continue to monitor week to week, my corals are so much more vibrant, showing signs of growth (expecially LPS), and things look so much clearer! I'll do one more water change to get it from 20 to 10 (around 150-160 gallon change.) I'm hoping the pellet reactor and matrix rock will maintain the nitrates once stabilized.

Based on my bioload and feeding, I actually expected nitrates to jump within a week's timeframe. The question I have is why didn't nitrates jump with the termination of vodka dosing? I love how clear the water is getting to be.

 

[hexcolor reef]

The homemade food was the issue. I switched to frozen krill and brine shrimp my self. I still have omega pellets when I don’t feel like breaking up krill but frozen foods helps with nitrate. Also I’ve used nite-out ll product. It’s mainly for start up tanks and ammonia but reading the label it says to use if you have a high nitrate problem. Great stuff. Fighting nitrates using bacteria can’t go wrong

 

[Randy Holmes-Farley]

Thanks for the observations.

I would note the following additional commentary:

1. All organic carbon dosing and pellets will tend to lower pH as the organcis are converted into CO2. One doe snto need to invoke clogging of powerheads to cause the pH lowering, although that may contribute.

2. The particulates in the water were likely bacteria, and switching to a different organic may have reduced or eliminated that issues if it instead drove benthic (surface-attached) bacteria. Skimming also tends to reduce the cloudiness, if any occurs. I did not detect cloudiness when dosing vinegar except at very high experimental doses.

 

[Treefer32]

Thanks for the observations.

I would note the following additional commentary:

1. All organic carbon dosing and pellets will tend to lower pH as the organcis are converted into CO2. One doe snto need to invoke clogging of powerheads to cause the pH lowering, although that may contribute.

2. The particulates in the water were likely bacteria, and switching to a different organic may have reduced or eliminated that issues if it instead drove benthic (surface-attached) bacteria. Skimming also tends to reduce the cloudiness, if any occurs. I did not detect cloudiness when dosing vinegar except at very high experimental doses.

I wouldn't say I had cloudiness. Maybe some, but by far the number of particles swirling in the water column towards the surface. I have high surface agitation due to 4 gyres mounted at the surface. 2 opposite ends of the tanks. That kept the oily surface clear, but it also kept particles constantly swirling at the surface. If there is a such thing as surface attached bacteria, my gyres probably didn't let them stay attached, but they constantly made their way to the surface, then back down again, then back up. Multiply that times thousands of particles. I still have some I'm hoping reduce over time, but, it's definitely getting better.

 

[Clownfishy]

When I dose NOPOX, I get an oily water surface. I used to dose quite high amounts of NOPOX and I also observed particles swirling at the top of the tank. Since installing a Tunze 9004 which surface skims, I no longer observed either. I came to the conclusion that if I had that amount of surface film, I was dosing way too much.

 

[Treefer32]

When I dose NOPOX, I get an oily water surface. I used to dose quite high amounts of NOPOX and I also observed particles swirling at the top of the tank. Since installing a Tunze 9004 which surface skims, I no longer observed either. I came to the conclusion that if I had that amount of surface film, I was dosing way too much.

This confirms / validates my findings as well. Thank you! The next thing to see is if with stopping vodka dosing altogether, the usage of my red sea rollermat decreases or not. So far it has not, at the same time, it may have a lot of bacterial slime to remove!