What fish to cycle tank?

[ilaizm]

I am currently setting up a 90G planted tank. Once tank is cycled, I am planning to have discus, rummy nose tetras, corydoras and bristlenose.

With what fish should I cycle the tank and how many?

[Mr Wild]

Do a fishless cycle. http://forum.simplydiscus.com/showthread.php?t=69594&highlight=fishless

[KDodds]

I agree. Cycling with fish is more than just an argument of "cruelty". Using a dozen or so fish that are going for $2-3 each is just wasteful expense when fishless cycling costs next to nothing and virtually guarantees that you will NOT lose fish to ammonia or nitrite during the cycling process.

[csarkar001]

if you do decide to cycle without fish, you may find it hard to find pure ammonia without a lot of additives. in the northeast where i live, the only one i eventually found was from ShopRite. ... and it worked twice extremely well.

[Eddie]

Cycling with fish can introduce nasty bugs to the tank. Kind of like a time bomb waiting to go off, once you you add the discus...BAM!!!! I know because thats what I did with my first discus tank. ;)

Eddie

[ilaizm]

Yes, a fishless cycle probably makes most sense, however, i'm not sure I will find pure ammonia in my country. Would I be able to order something like that online?

[Patr1ck]

It doesnt have to be pure 100%. I used 10% janitorial strength. It didnt say but I'd be willing to bet it had surfactants in it too. It worked fine for me. I got mine from a local hardware store. Grocery stores have it too. Just make sure it doesnt foam like soapy water when you shake the bottle. I should look like rubbing alcohol when you shake it. It also has to be crystal clear. I changed 100% of the water twice before I added fish.

Pat

[Don Trinko]

I have done it both ways. It can be done humainly with fish but there are many disadvantages.
1. to do it humainly you use just a few fish. The ammonia and nitrites will not get into the danger zone IF you do it correct. I did this with a SW tank and the ammonia never got higher than .5, nitrite 2.
2. Since you use very few fish the bioload will only suport a small addition of fish without causing another cycle. This means that if you add more than one or two fish at a time you will get a mini cycle.
The big advantage to using a fishless cycle is that you can control the amount of bacteria by the ammount of ammonia you add. If you use enough ammonia you can add all the fish at the same time. Don T.

[ApacheDan]

This might sound tough.....but it's life. I know of some people that breed discus and just select their best for sale. The ones that are seconds or culls are kept on a separate tank for......you guess, cycling tanks.:(