Discus keeping revisited - and some questions

As a teenager in the 70's (go on, work it out :-)) I loved keeping discus (at the time my tank was on top of the cupboard in my bedroom!). When I went to university a few years later that hobby went away (soccer, girls and even the occasional study took over!!). I had another stint with discus keeping in the early 90's before my wife and I relocated to the US (we are displaced Brits). I enjoyed my discus back then and had them breeding, albeit without getting to the stage where I actually saw fry (we moved to the States as I was investigating the cause of the eggs frosting over). Anyway, to cut a long story short I am interested all over again, this time with two girls (aged 8 and 10) who have an interest. Through the generations...

I bought a nice Oceanic 72 gallon bow front aquarium over the weekend. I am very happy with the look of this thing in my living room - it's very functional as both a fish tank and a focal point for the room.

My PRIMARY goal is to build a really attractive discus tank with stellar discus. It would be cool to one day see them breed - but that is a secondary priority to the overall desire to see healthy, beautiful discus happily swimming around in my living room setting. So, I am not interested in an empty aquarium (no substrate, plants, etc) - the look is very important. That said, I have found artificial plants to be perfectly acceptable and have installed a bunch this evening. A relatively low maintenence schedule is also a goal, within reason of course, hence the preference for artificial plants.

I installed a Fluval 404 filter with the provided media - sponge for mechanical, carbon for chemical and those bio-cylinder things (can’t remember the precise name) for biological. I have two heaters, heating to 82 degrees. After a day or so of running the filter (filled directly from the tap, with an addition of a ph 6.5 powder and Cycle) I purchased a few fish to get the cycle under way (4 serpae tetra and 4 silver-tipped tetra). At this point, I have a ph of 6.5 and ammonium, nitrite and nitrate readings of zero (after two days with the fish). The new additions are eating and swimming around very happily. Here are my questions...

Am I correct in saying that I should expect an increase in ammonia FIRST, then nitrites and then nitrates?

I know ammonia and nitrites should be kept to a minimum in an established tank (readings of zero?). What about nitrates? What's a "good" reading?

When should I expect to see the cycle get under way in earnest, given the size of my tank and the initially small number of fish.

How do I know when the cycle is ‘done’ (ready to add discus)?

Once ready, how many discus would you suggest I initially add? I have seen widely varying suggestions and want to shoot for at least 4 full grown discus (I will buy them smaller). Feasible? What about more (8 would be nice)?

I am, of course, very eager to pick up my first few discus, as are my kids! But I also want to do this right! I’d very much appreciate any comments on the questions above.

Thanks in advance.

Mark