p.s. kinda liked miss wiggle's authority - does that make me wierd!!
well you see nutrafin cycle is a great idea, the filter comes as a bit of hardware, like a pc with no software on it or something, it's got all the kit to do the job but doesn't just plug and play, it needs preparation for the bacteria that live in it to grow and only after that point will it do it's job and keep the water clean. There's no magic trick to filters, they're basically a pump and some sponge, and that by itself will not process fish waste and convert it from toxic ammonia to 'safe' nitrate, you need the bacteria there or it doesn't work.
So what nutrafic cycle claims to do is to put the bacteria in there instantly meaning that the filter works within a week and you can then skip the whole cycling phase. Great idea, shame it doesn't work.
Bacteria are a living organism, they will not live indefinately on a shelf in a fish shop with no food or oxygen. By the time the bacteria have been packed, gone through the factory processes, been packed, sat in a warehouse for a few months, been distributed to the pet shop and then sat on a shelf for months there's nothing left alive in them.
So even when you have added the cycle you'll add fish and find that the filter doesn't work. It turns the water over in the tank but the water quality very quickly deteriorates and then the fish start getting ill. What we do for a fishless cycle is we add ammonia to the tank, thsi simulates the fish waste going in, the bacteria feed off the ammonia and will start to grow, we measure the water quality over a couple of weeks and then we can tell when there is enough bacteria there to consume all the fishes waste. So we then add fish and have no problems with water quality.
I don't want you to feel like we're really getting on to you, it can seem very daunting for beginners and sometimes it's hard when someone tells you that the 'experts' at the fish shop don't know what they're talking about. But to put it into perspective, even the real senior guys in the lfs are on a small amount over minimum wage, these are not qualified marine biologists, they're salesmen. The industry is barely regulated meaning just about anyone can sell anything. There's a lot of genuine hobbyists here who are really smart people who would dearly love to work with fish all day, but the reality is that it doesn't pay so we have to do other jobs.
All we're trying to say is please don't take it for granted that this bottle of stuff the fish shop have sold you will instantly make the tank safe for the fish. If you decide you want to do a fish-in cycle then that's your choice, but make it a conscious choice rather than being dumped into a situation because you didn't do the research or just believed the fish shop. It will just take you 10 mins or so to read through the two links in my signature 'whats cycling' and 'fishless cycling' if you still decide to get your fish after a week when you've read them and understand what you're doing then that's a different matter. But please just read them first.