Fishless cycling question...

Basically I'm trying to figure out what kind of bioload (i.e. how many fish) can be initially placed in a tank that can cycle 5 ppm Ammonia in 24 hours?
Extra Credit question: What kind of effect does this kind of cycling have on plants?

The reason I ask is I have read about this kind of cycling several times, but none have been specific on how many fish this was meant to support.

To be a bit more specific I'll give an example of what I would want to do:
60 gallon tank
Well planted
6x 3-in Discus Fish

I wanted to get all 6 at once due to the fact that the breeder is several hours away (none of the LFS are willing to carry such an expensive and "difficult" fish), and this helps ensure that the school contains fish that are all similar in size. The added benefits of going to the breeder myself of course are that I can see them before I buy them, get a better idea of the water conditions the fish were used to, and know exactly what kind of foods they were being fed since Discus are apparently picky eaters.

I'm trying to be extremely cautious and gather as much info as possible before I sink $30-45 into each fish!

Thanks. ^^ I was planning on doing several "small" water changes each week anyway since Discus prefer very clean water.

I was just curious about what kind of bioload (using the inch of fish to gallon ratio) 5 ppm Ammonia would represent since it seems to me that would be a handy thing to know. Obviously different fish have different metabolism rates which effects the amount of ammonia they produce (tropical vs goldfish for example), but a general idea would be nice. ^^