Offering your fish a little tipple might not seem like a solution to the problems brought about by nitrates and phosphates in the water but those in the know understand that by adding ethanol…otherwise called vodka, the quality of the water in most notably, reef aquariums will improve.  This common method of improving water quality has been well tried and tested by many fish keepers and is recommended by most. The idea behind it is that by adding an inorganic carbon to the water, bacteria which will consume nitrates and phosphates is encouraged to grow in profusion. As soon as the bacteria grow to a reasonable size, they will be removed by the skimmer.

The reason behind the use of vodka rather than any other alcohol is pretty clear…literally! Vodka is a very pure form of alcohol and as long as hobbyists add it in very small amounts and follow general advice and guidelines, there should be absolutely no ill effects to the fish whatsoever. So the thinking behind vodka dosing is that by adding a source of organic carbon (vodka) the excess nutrients in the tank are reduced. Potentially harmful nitrates and phosphates are the worst offenders in terms of damage and it is these which vodka dosing will target; once phosphates are reduced the growth of corals will usually improve.

So it seems very simple…add vodka and instantly see improvement; however, it is advisable to use extreme care when introducing vodka to any system because the fact is that the amounts to be added must be carefully calculated or you could actually cause damage to your system. Before thinking about adding vodka to your system you should ensure that you have a good quality skimmer in situe; the skimmer removes the resulting bacteria once it has done its job…a good skimmer will produce a nasty looking sludge as it removes the resulting bacteria from a system which has had vodka added to it in the correct amounts.

Caution is advised when it comes to adding vodka to your system due to the fact that an overdose can result in not simply the deterioration of the water quality in your tank but also in the death of fish. One of the unfortunate side effects which can result from miscalculating the amount of vodka to add to a tank is the acceleration of the growth of coloured, dissolved, organic matter or CDOM. This is usually yellowish when found in tanks and in order to combat the potential for it’s increase, some experts advocate the use of ozonators to help break down the matter which has built up. Another option is to simply add granulated activated carbon which will help to rid the system of the CDOM as effectively.

The recommended dose of vodka is no more than 0.1ml per 25 gallons and this should be carried out for three days. After this initial period, the dose should be doubled to 0.2ml per 25 gallons for a period of four days and from then on, an additional dose of 0.5ml should be added no matter what the volume of the tank happens to be. At this point it is recommended that water quality is tested and if things are going well then the amount of nitrates and phosphates present should have decreased.

As soon as you detect a decrease in nitrates and phosphates then cut the dose in half and continue in this fashion until you can barely detect them at all. You may now assume that it is safe to continue in this way all the time observing the inhabitants of the tank for signs of stress. If you do see signs of stress at any point during the dosing period, you should cease the regime immediately and remember never to double up on a dose if you have missed one.

If you are uncertain about vodka dosing, check with your suppliers and be sure that you have an good quality skimmer installed before you begin!

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