My Fishless Cycle Log

[OldMan47]

You need to be careful with the nitrite test. If the drops change color as they fall to the bottom of the tube and then the color dissipates to a pale color, it is too high to measure, not near zero. It is a trap of the way the test works on high concentrations, but it has caught lots of people who didn't know better.

 

[soccermatt]

Finally my cycle has completed an i would like to add a fish or two tomorrow, but first i have a couple of questions.

1. I cycled with fish food, and haven't done a water change since i started really. I know i should do one and get all the gross fish food off the bottom and gravel, but i know that the bacteria will die without an ammonia source. Would i be all right to do a large water change this evening, and get fish around mid-day tomorrow, or do a big water change tomorrow morning, the same day that i get the fish.

2. I know there is a fair amount of bacteria in the gravel, so would it be safe to do a decent gravel vac before i get the fish?

Thanks

 

[waterdrop]

There's nothing wrong with doing both of those things. Do a large gravel-clean-water-change to get the excess food and nitrate out and then refill with conditioned, temp-adjusted water and introduce fish mid-day tomorrow. The bacteria in the gravel are tightly attached to the gravel and won't be lost by a gravel clean (however, they really aren't nearly as significant in numbers as the bacterial biofilms in the filter biomedia. The bacteria are very slow to start dying off at first (from lack of ammonia) and it won't be a problem at all to go this time period.

You'll need to continue twice daily testing for ammonia and nitrite(NO2) after you introduce your fish to make sure the toxins stay below 0.25ppm in each case. New setups are not necessarily stable and not really mature until about 6 months out.

~~waterdrop~~