Looking for feedback, Vodka / Carbon Dosing, Big Tank, Big Nitrates

[Bill1119]

That is a great video, very much to the point,

Makes a good pitch to use vinegar rather than vodka, and it would be easier to control precisely with a dosing pump,

They are not so discreet about dosing volumes either, suggesting a larger starting dosage, and larger weekly increases.

There is a good disclaimer on making sure the phosphates are in range, for the appropriate bacteria consumption rate between nitrates and phosphates.

[Frogger]

Whats your phosphate

[Llorgon]

I have been dosing vodka in my 25 gallon tank since February. Before vodka dosing my nitrates were around 40ppm and phosphates around 0.084. As of last week nitrates were 1.5ppm and phosphates 0.009ppm.


I followed the same 0.1ml / 25 gal for 1-3 days, then 0.2ml / 25 gal for 4-7 days then increased 0.5ml per week after that. My largest dose was 1.2ml which I kept up for 2 weeks.


While vodka dosing I have also cut back on the amount I was feeding, tried to feed more pellets instead of always frozen. Also did large weekly water changes where I vacuumed the sand and turkey basted the rocks.


I also double checked my water supply to make sure it was nitrate and phosphate free.


I found it took awhile for things to start to drop, but once it started I would notice a significant drop each week when I was testing. It took about 1 month for me to start seeing a drop. So it's not surprising it's taking awhile to drop in your tank.



If you stick with it it should start working! Good luck.

[Bill1119]

Thanks for the feedback so far!

Phosphate is at 5 ppm, tested with Red Sea Pro Kit,
I used a 1 ml tank water to 16 ml RO/DI water ratio and extrapolated the base 0.36 reading to 0.36 / (1/17) = 6.12

I tested the RO/DI water with no dilution and got a reading 0.08ppm.
To adjust my reading above, 0.08 / (1/17) = 1.36
(there may have been some contamination as I tested the tank water first, but I think this value is correct, my RO Membranes are 3 months overdue on changing)

Also of note on the Nitrates, I had tested the RO/DI water and got a value at or near 0, I was on the fence whether it could be called a 0 or 0.25 on the Red Sea Pro test kit.

I do strongly believe that the dosing works, as I had started with the process once previously.

You are correct that my water supply is not perfect but it is not bad in comparison to the tank parameters, and I have seen the water supply quickly correct when the RO filters are changed after a year of use. It is on the list to correct before driving substantial water changes again.

I intended to turn the tides on the nitrate and wait till it starts dropping before adding larger water changes, currently 50 gallon every 2 month, and will move to 50 gallons 4 times or more per month.


Llorgon, my initial post was specifically directed towards your experience and that it is generally accepted in the hobby to increase the vodka dose by 0.5ml per week on a 25 gallon tank, (after the initial week)

I am specifically asking if there is a reason this limit is set regardless of size of tank. (of 0.5ml per week)

On a 25 gallon tank you would have Day 1-3 @ 0.1ml, Day 4-7 @ 0.2ml, Week 2 @ 0.7 ml, Week 3 @ 1.2ml
From week 1 to week 2, the dose increase is over 2 times the week 1 dose, and even as a percentage from week 2 to week 3, the increase is 70%

For my system on this scale I am using 300 gallon system volume. Day 1-3 @ 1.2ml, Day 4-7 @ 2.4ml, Week 2 @ 2.9ml, Week 3 @ 3.4ml
From week 1 to week 2, the dose increase is almost 1/5 of my week 1 dose, and from week 2 to week 3, the increase is 17%


Based on my research the last 2 weeks, I am genuinely considering the following dosing,
Day 1-3 @ 1.2 ml
Day 4-7 @ 2.4 ml
Every 4 Days, Increase the Dose by 1.2 ml
(Or increase by 1 ml increments for ease of adjustments and a little bit of conservatism)

I understand that this is not endorsed by any reputable articles that I have seen, and wanted to see if anyone might disclose when they went to fast ( i have seen a few of those disclosures but never the details)

My Tank is 28 x 28 x 84 (inches), with 2 beveled corners (maybe 10 gallons lost) and the sump is 72 x 24 x 19, with a nominal water level of about 12 inches.

If nothing else I can let you guys know how it goes!
Still on the fence on risk, and not expecting anyone to say jump in, but hoping to hear the experiences like yours Llorgen, Thanks!