Hello and Questions

I am reintroducing myself to the hobby. My name is Clifford King and I am a second year veterinary student up in Washington State. I grew up in Utah and attended Utah State University until moving up here for more school. While at USU, I started and kept a 90 gallon tank that had a 40 gallon refugium. Now, I am have started a 29 gallon biocube. I went with the biocube because it seemed like it didn't need a lot done to it to start a mini reef. I set up the tank about 3 1/2 weeks ago. It has 40 lbs of LS, 30 lbs. LR and 5 hermit crabs. The Nitrate levels are finally back to 0 and I had a small diatom bloom about a week ago that is almost gone and I added a clown yesterday. That being said, I have gotten a lot of information from my LFS and a fellow class mate that I need to change out everything. So, I come to you with questions.

To start off, I envision my tank eventually with a wide aray of different zoanthids, a hammer coral and a frogspawn, Along with 2 clowns, a cleaner shrimp, and a diamondback goby. Does that sound reasonable?

Should I change out the bioballs (origianlly I took out about half of the ones that it came with)?

Do I need to add a protein skimmer? IF so, what seems to be the best that will fit in the back compartment?

Should I add on a light on the back and add ceulerpa/ chaetomorpha?