If you are doing a cycle with fish you have to choose hardy fish that can withstand the chemical chnages in your water, a lot of people will suggest the fishless cycle and there are thread (I am sure someone can post the links) for the fishless cycle on the site.
I personally go fishless, but that is my choice and it is up to you which way you go.
If you are using fish danios are hardy as are platys, I believe you can also cycle with mollys - but I couldn't verfiy this and also a lot of people would suggest adding salt with mollys as they like brackish water - but them other peeps will tell you they do fine in FW. - Lol, sorry to be confusing.
I know for definite that danios can cycle As can platys. Be sure with the danio though to have a little group as they are schooling fish, and with platys I believe a 1 male to 2 female ratio works best otherwise a single female will be harrassed to death by the male as they are livebearers and most of them seem to like a 1-2 ratio.
Exact numbers of fish are hard to say without knowing the size of your tank, also have you added the de-chlorinator? I personally would do that and leave the tank up and running for a week without fish - even if I was doing a cycle with fish, mainly just to make sure all the equipment works properly and it gives the water chance ot settle and any cloudyness etc to disperse.
I am sure there will be other more expert peeps along soon to help out where I can't.
hI luke I would go with the fishless cycle, that's what I am doing at the moment, ours will be ready on sunday for the new arrivals! I can't wait. also definitely go with the 2 female to 1 male as when I first got my other tank I didnt have much knowledge on what I was doing and I had 5 males 1 female and they harrased my female platty so much that they killed her. by the way did you manage to sell your other tank? sorI I couldnt buy it off you. emma x
It is much nicer to the fish to cycle fishless. You can do this by adding a pinch of flakes twice a day, or if you can find it by adding pure ammonia. Once the tank is cycled, you can add fish. This saves fish from having to suffer through toxic ammonia and nitrite levels which often kill them, it doesn't take as long as cycling with fish, and it is much less work because you don't have to test the water daily and do constant water changes. Please consider this carefully, as it is much more humane for the fish. If you still want to use fish, Neons are definitely not good choices. You will need to pich extremely hardy fish, add them very slowly, test your water daily, and do water changes frequently in order to improve the fish's chances of surviving. That is way more work than I would want to do, as well as endangering the fihs, but it is the traditional method and some people like to have fish right away I guess.
To answer your question, a school - although if you want to get technical, it's actually a shoal : (although most people just use them interchangably) - anyway it consists of at least 6 fish. With tetras having more than that is sometimes suggested as it makes a fantastic display. The exception is some catfish--Cories and Otos--which will shoal nicely in a larger group but seem to do well in groups of 3 or more.
Well, let us know if you have any more questions, and have fun with your fishies!
you save a lot more money by fishless, too! you don't have to replace tons of dead fish :'( and please don't do a fish cycle with neons, they used to be pretty tough fish but nowadays inbreeding has weakened them so much that they are sensitive to even small amounts of ammonia and nitrites. I did a fishless cycle, and my neons died within a few days just from the stress of moving. the second try failed too, just from the shock of a new tank.