well i will start at the beginning!
you will need
1.at least a 20 gallon (100L) tank witch will hold 2 clowns as with saltwater tanks you need to allow 10 gallons per fish
2.a Good Quality Filter (i recommend a wet/dry trickle filter)
3.heater
4.sand
5.live rock
6.protein skimmer
7.good quality lighting (t5 or metal halide)
8.hydrometer (to measure salt)
9.powerhead
10.master saltwater test kit
11.filter media and bio balls
12.clean up crew (snails,hermit crabs, shrimps, sea urchine)
then when you have set all this up you need to start to cycle the tank as it has to complete the nitroge cycle before you can add any fish and this takes between 6-8wks you can do this by adding pure ammonia to the water until it shows between 5-10ppm on an ammonia test! then let it cycle for 2wks and then do an ammonia test once this comes back at 0ppm you need to start testing for nitrites once this comes back as 0ppm you can test for nitrates and this should be below 25ppm at all times it will creep up in water over time and the live rock will help but the only real way to keep on top of it is by weekly water changes! and yes you always mix the marine salt mix and water in a seprate large tub before adding to the tank also you need water that has been filtered by a RO unit witch removes the trace minarals from water and also phosphates witch cause uncontrolable algae!
now breeding clownfish is extramly hard work you will need atleast 6 tanks and all for differnt stages of there life to adulthood
i have a breeding pair of true percula clowns and they still havent laid any eggs as the stress of moving them has messed up there breeding cycle i have also spent over £20,000 (about $40,000) on the set up and still waiting
they need plantonic food like rotifers when they are new fry and then they need feeding in turn and you will need a baby brine shrimp hatchery and 6 tanks to let them go in to a they grow as there will be the next lot on the way and the fry tanks cant be filtered and need water changes 3-4 times a day and the fry need feeding 6 times a day and you get a very high death rate out off 400eggs you may only end up with 50 adult fish
think about it hard as if you cant keep other fish alive this is not the hobbie for you
you need to do more research