Welcome back
what you have got will do you for now and will work
Laterite is still used today and those that are into their plants still use it.
A good source for gravel is Stone and Water World on Marua Rd, Ellerslie
Good fish shops are:
Hollywood Fish Farm, Frost Rd, Mt Roskill
Jansens, Mt Eden Rd, Three Kings
Bird Barn, Lincoln Rd, Henderson
Massey Pets, Don Buck Rd, Massey
Pupuke Aquarium, Lake Rd, northcote.
Jansens, Ti Rakau Dr, Botany
With regards to cycling... yes you are on the right track
Jansens, Porana Rd, Glenfield
Goldfish Pagoda, Cascades Rd, Pakuranga