Vodka dosing calculation all wrong?

[Randy Holmes-Farley Verified Community Expert]

Do you know that the nitrate value is real, and not interference from a small amount of nitrite?

 

[MnFish1]

While the 50% reduction sounds right/great in theory, for me it has not worked this way. I have been diligent about changing water every 5-7 days, and I do not get a 50% reduction each time. If I did, by now I'd be probably under 5 or 10ppm but I can't seem to get below 50ppm. In fact, since my last water change, the nitrates have gone up, but that could be from me feeding the corals.

I don't think you understand what I mean.

I mean - you change let's say 50% of water right before your nitrates are 200 (I know you are now thinking they might be higher so what you're saying makes even more sense). If you immediately change 50% - and check the nitrates they will be 100. IF for some reason your tank is producing more nitrate that usual if you check it in 5-7 days - it could be 80 or 100 again - or even 200.

Assuming your tests are correct, What I would do is 1) Recheck your source water - is there nitrate in there - pre and after mixing. 2). change 100% of your water and measure nitrate daily for 7 days. This will give you a good idea of the rate of production. 3) I would stop dosing things for now since it just adds another variable.

I'm guessing that some things on your rock died during transfer (not sure how you did it) - and produced ammonia which is being converted to nitrate.

PS agree with @Randy Holmes-Farley that there could be an interfering substance. However, if you change 100% of your water - your nitrate should be zero (as will be the nitrite) - then perhaps measure nitrite and nitrate every day or every other day.

 

[SteveMM62Reef]

Vodka Dosing didn’t work on my less than a year old Aquariums, worked wonders on my GHA, on an older set up. I couldn’t figure out what it was feeding on. Anyway, you are too new on your Vodka Dosing to see results. I ramped up 1/2 ml Per week, on my 62 Gallon, till I hit 8ml. Didn’t really start seeing results till I was at 6ml. I’m not sure if 8ml is my balance point BTW, I have plenty of live rock, and a GFO Reactor Running. What ever you do don’t start dumping a bunch of Vodka in, know someone who killed off their entire tank doing that.

 

[tanks2u]

I don't think you understand what I mean.

I mean - you change let's say 50% of water right before your nitrates are 200 (I know you are now thinking they might be higher so what you're saying makes even more sense). If you immediately change 50% - and check the nitrates they will be 100. IF for some reason your tank is producing more nitrate that usual if you check it in 5-7 days - it could be 80 or 100 again - or even 200.

Assuming your tests are correct, What I would do is 1) Recheck your source water - is there nitrate in there - pre and after mixing. 2). change 100% of your water and measure nitrate daily for 7 days. This will give you a good idea of the rate of production. 3) I would stop dosing things for now since it just adds another variable.

I'm guessing that some things on your rock died during transfer (not sure how you did it) - and produced ammonia which is being converted to nitrate.

PS agree with @Randy Holmes-Farley that there could be an interfering substance. However, if you change 100% of your water - your nitrate should be zero (as will be the nitrite) - then perhaps measure nitrite and nitrate every day or every other day.

I understand what you're saying now. I don't have the capability to change 100% of my water at once, so I'd have to break it up over 2-3 days.

 

[tanks2u]

Vodka Dosing didn’t work on my less than a year old Aquariums, worked wonders on my GHA, on an older set up. I couldn’t figure out what it was feeding on. Anyway, you are too new on your Vodka Dosing to see results. I ramped up 1/2 ml Per week, on my 62 Gallon, till I hit 8ml. Didn’t really start seeing results till I was at 6ml. I’m not sure if 8ml is my balance point BTW, I have plenty of live rock, and a GFO Reactor Running. What ever you do don’t start dumping a bunch of Vodka in, know someone who killed off their entire tank doing that.

I haven't dosed vodka since Saturday night, and I didn't have plans to restart.

 

[tanks2u]

So, I'm about to begin a large water change and decided to check nitrates before starting. It's at 64.9ppm which is what it was 2 days ago, so it doesn't seem to be increasing. I'm going to take that as a positive, since it hasn't increased. I'll test again after changing water. Wish me luck.

 

[MnFish1]

So, I'm about to begin a large water change and decided to check nitrates before starting. It's at 64.9ppm which is what it was 2 days ago, so it doesn't seem to be increasing. I'm going to take that as a positive, since it hasn't increased. I'll test again after changing water. Wish me luck.

Yes - that would be the implication!!

 

[killer2001]

If I was in your shoes, I would do the following:

- Get PO4 into a range of about 0.1ppm to 0.2ppm.
- Carbon dose 10mL vodka daily for a week.

Check nitrates on day 1 at a certain time, and then again on day 7 at same exact time as day 1.

- If nitrates still rising higher, increase to 20mL vodka, rinse and repeat.
- If nitrates about the same, increase to 15mL, rinse and repeat.
- If nitrates slightly lower, maintain dosage at 10mL.
- If nitrates much lower, decrease dosage to say maybe 5mL.

Of course, make sure your skimmer is running and oxygenating the water and also pulling out the bacteria accumulated by the carbon dosing.

 

[MnFish1]

If I was in your shoes, I would do the following:

- Get PO4 into a range of about 0.1ppm to 0.2ppm.
- Carbon dose 10mL vodka daily for a week.

Check nitrates on day 1 at a certain time, and then again on day 7 at same exact time as day 1.

- If nitrates still rising higher, increase to 20mL vodka, rinse and repeat.
- If nitrates about the same, increase to 15mL, rinse and repeat.
- If nitrates slightly lower, maintain dosage at 10mL.
- If nitrates much lower, decrease dosage to say maybe 5mL.

Of course, make sure your skimmer is running and oxygenating the water and also pulling out the bacteria accumulated by the carbon dosing.

All good. But - there is no need for vodka. Many people do not use it and don't have this problem - I would say - get the level down to a stable amount - THEN - after a week or so - if you nitrates are increasing - try vodka. Vodka is not a necessity to run a reef tank.