Where do you live? If you're local, I wouldn't mind helping you out.
You have to keep in mind, that the colorful tanks that you see are mostly well-established tanks. They didn't come out like that in 1 or 2 weeks. Most tanks don't really start taking off until after a year, when the parameters are stable enough and there are no more cycles going on. I've seen local reefers throw thousands of dollars on corals only to quit less than a year into the hobby because everything starts dying. You need to slow down.
Let me offer some quick tips:
-Get a refractometer and calibrate it properly with a solution.
-STOP dosing too many chemicals.
-STOP bothering your corals. Leave them alone and let them settle.
-DO use RO/DI and a good salt (I use IO)
-DO stabilize your temperature
-Consider getting a controller for more stability. I use an RK2. Best investment ever, IMO.
-Monitor your fish
-Monitor your corals for disease and pests (AEFW, Monti-eating Nudis, and Red Bugs)
-STOP dosing chemicals!
-DO check where you get your stock. Are they already bleached to begin with? Are they wild-collected? Did you acclimate them properly? What was the lighting in the store display? Were they cut from the mother colony or acquired as frags? What were the water parameters of the store compared to yours? (a huge variance CAN and WILL shock the specimen and may kill it eventually)
-What species did you acquire? I recommend starting off with a few hardy SPS... M. Capricornis, M. Digitata (green), A. Valida, A. Micropthalma, and A.Yongei (green slimer) are all very hardy in my experience. Corals like A. Verweyi, Lovelli, and some deepwater acros are not very easy to keep. Selections DO matter.
Take a couple of hardy SPS frags and grow them with nothing but regular saltwater. I agree to the poster above to limit your water change to encourage more stability. You would cringe but I only do 10g water change every month.. and that's enough for me. Once your frags start encrusting and your system is more stable, you can slowly start adding more. Overtime you will learn how to "read" your system without even using test kits. This takes time, but I was like you too when I started. Don't get discouraged, you'll get it eventually.
And lastly, if you can post a pic of your tank, your sump, and your equipment, that will be a big help and maybe some of us can make comments and suggestions.