Ideally I want 15 Tetras but was advised to slightly overstock to ensure the bacteria already established was well 'fed'.
Hi Stormy,
I think it was me who advised that, but not to keep your bacteria well fed. I suggested you should stock the tank a bit heavier than you had planned, as one of the benefits of fishless cycling is that you should be able to fully stock the tank all at once, should you want to do so. However, this benefit is lost soon after the fish are added and bottled ammonia is stopped as the excess bacteria start to die off due to lack of food.
To give an extreme example, if you now stocked your tank with 3 tetras and didn't add fish for say 2 weeks, your excess bacteria would have died off and you would have enough bacteria left to process the waste from your 3 tetras (this is what always happens, supply meets demand if you like). Now, when you come to add more fish, the bacteria can double in around 24hrs as Tolak mentions, so really the most you could add at once would be another 3 tetras, if you are to avoid mini cycles.
Had you stocked 20 tetras at the outset, you wouldn't have this problem and could quite safely stock another 20, rather than 3.
In fact, (extreme again) you could in theory stock so lightly (say 1 tetra) that the benefit of fishless cycling would be almost lost altogether, as you would experience mini cycles each time you add additional fish (same as you would with a fish-in cycle).
I was recommending stocking more heavily on that basis, as it is a benefit exclusive to fishless cycling (as opposed to fish-in cycling) and its a shame to lose it. Why take 10 weeks to stock the tank and risk ammonia spikes when you can do it in 1 day with virtually no risk?
If you only want 15 tetras, obviously don't stock 20 tetras, but stock as much of your stocking list as you can at the outset to retain the benefit you have well earned.
Anyway, this could be another thread in itself, so i digress..........
Cheers
BTT
