I can tell you that this is not a cheap hobby.. Do a search on the site there are severl new posts on setting up new tanks.
Dory is a Hippo Tang or Blue Tang they need a large tank, 100+ gallon for them to do well.
You will need test kits, Salt, hydrometer, IMO LR
is a must have for good natural filtration, I like skimmers on both reef and Fish only tanks, lights a PC
light would do well for a FO
tank. Cutting corners usually ends up costing more money in the long run.
Save up your money and do lots of reading on SW
tanks and in 6-8 mouths you may have enough cash to jump into the hobby.