Aquarium setup & gravel selection

Question
Hi,

I'm a first time fish owner, to answer all the instructions:
I have roughly a 110-125 gallon tank (I know, not the best choice for a newbie), Currently don't have any fish but already have arrangements for a pair of discus, a few crayfish to keep the floor clean, a few Cynotilapia(African Cichlids), a 2 or 3 goldfish and some freshwater plants. (its a freshwater set up). For filteration there are 2 fluvial 304 filters and one aquaclear 300, tank is roughly a year or two, first time use as an aquarium, no leaks and so far no water change schedule (need information before i fill it up).

My questions are:
1- Can i use outside gravel (patio use, etc) as gravel in the aquarium, Washed riverstone pea gravel?

2- Does that combination of fish sound suitable or will I eventually be left with one gigantic and hungry fish?

3- Please give me whatever advise, as a newbie, to set this up and for good up keeping.

Thank you very much for your time and help.

-Zubair

Answer
1) Gravel should never be used with discus. Discus need PRISTINE water to grow properly, with gravel you will be doing water changes literally EVERY day. Use aquarium sand instead, sane is cleaner and 80% water changes every other day are good.

2)Discus are ok, but not a good choice for a beginner, really.

Crayfish will not mix with discus, no way. Maybe with goldfish though.

African cichlids are probably the worse thing you could add to a discus tank, they will rip the discus to shreds in seconds. Africans can not be mixed with anything other than other africans.

Goldfish can not mix with discus. They are coldwater, discus are tropical.

3) Join the forum in my signature and ask your questions there, you can ask as many as you want and they will all be answered, I can only really take a couple questions a day.
I think a goldfish tank would be your best bet as a beginner. But do more research first.

-Nick