Hi Kano, welcome to the saltwater world!
If you're going to keep fish only in your tank then you'll be fine with your tank, heater, regular filter, aquarium salt and 2 clowns but I wouldn't recommend the tangs - they get too big for a 35 gallon.The need a minimum of 75 gallons so maybe save up for a bigger tank if you want them!
I would definitely get some
live rock too - it acts as a brilliant filter and you'll often get some great little hitchhikers on it like asterina starfish and feather tube worms.
Other equipment: You'll have to get a water
test kit for
phosphate,
nitrate,
nitrite and
ammonia as well as a
hydrometer whcih measures the level of salt in your water.
Bear in mind you'll have to cycle the tank for a while so you can speed up the process by adding live rock right from the beginning and if you can get some
live sand that always helps. Make sure your water parameters are steady before you add any fish at all because you dont wanna harm your little clowns
Any questions feel free to ask!
Urs