When using Prime I treat the amount of water being replaced rather than entire tank volume (e.g., when doing a 50% water change on my 180gal I add 9ml; when doing a 50% water change on my 5gal I add 0.5ml, instead of 18ml and 1ml respectively) and have never had any issues. I add the Prime in the tank prior to adding the new water.
The way I see it, Prime not only works near-instantaneously, but there's also the dilution-effect of the remaining tank water to consider. Chloramine-treated tap water is diluted as it enters the tank by the established aquarium water volume while simultaneously being detox'd by Prime.
For example, by sheer existing tank water volume alone, when doing a 50% water change on my largest tank, the first gallon of chloramine-treated tapwater entering the tank (via th Python) is diluted to approximately 1/90th its concentration (chloramine being reduced from 3ppm to 0.03ppm). With 9ml's of Prime (enough to treat 90gals) already in the aquarium, that 0.03ppm of chloramine for all intents and purposes is neutralized as soon as it enters the tank. Not only that, but the dilution effect increases as the tank fills (the last gallon entering the tank being diluted to approximately 1/180th (e.g., 3ppm chloramine diluted to 0.016ppm, then detox'd by Prime).
The same principle applies to my smallest tank (10gal) containing my most fragile and delicate fish (which are newborn fry) and works with no adverse effects (I'm currently growing out the 'great-grand fry' of some store-bought fish purchased years ago, so this method has worked for me through several generations of fish). I remove half of the water (5gal), add 0.5ml of Prime to the tank and then add tap water in half-gallon increments, with dilution and dexotification of chloramines occuring concurrently.
For temperature control I use a digital thermometer (which is accurate to one-tenth of a degree). I place the probe about 6-8" away from the incoming new water and adjust the temperature if it shifts more than a degree.
The way I see it, Prime not only works near-instantaneously, but there's also the dilution-effect of the remaining tank water to consider. Chloramine-treated tap water is diluted as it enters the tank by the established aquarium water volume while simultaneously being detox'd by Prime.
For example, by sheer existing tank water volume alone, when doing a 50% water change on my largest tank, the first gallon of chloramine-treated tapwater entering the tank (via th Python) is diluted to approximately 1/90th its concentration (chloramine being reduced from 3ppm to 0.03ppm). With 9ml's of Prime (enough to treat 90gals) already in the aquarium, that 0.03ppm of chloramine for all intents and purposes is neutralized as soon as it enters the tank. Not only that, but the dilution effect increases as the tank fills (the last gallon entering the tank being diluted to approximately 1/180th (e.g., 3ppm chloramine diluted to 0.016ppm, then detox'd by Prime).
The same principle applies to my smallest tank (10gal) containing my most fragile and delicate fish (which are newborn fry) and works with no adverse effects (I'm currently growing out the 'great-grand fry' of some store-bought fish purchased years ago, so this method has worked for me through several generations of fish). I remove half of the water (5gal), add 0.5ml of Prime to the tank and then add tap water in half-gallon increments, with dilution and dexotification of chloramines occuring concurrently.
For temperature control I use a digital thermometer (which is accurate to one-tenth of a degree). I place the probe about 6-8" away from the incoming new water and adjust the temperature if it shifts more than a degree.
