65 gallon, 3 feet - you can do a lot with a tank this size. What kind of aggressives do you like?
Do you want a tank with quite a few smaller fish, or one or two large "pet" fish with lots of personality? What's your budget like?
What kind of environment do you want?
I have a green wolf eel blenny in a 55 with other fish, have had it at least three years. Not a true eel, or a blenny, it's related to dottybacks. Very interactive, an aggressive eater, doesn't get huge, and doesn't bother the other fish in the tank. Less aggressive than I expected, as far as being a model citizen (a good thing).
Here are two good articles:
http://reefkeeping.com/issues/2005-04/fm/feature/index.php
http://reefkeeping.com/issues/2004-04/hcs3/index.php
Some others you can consider - some compatible, some not:
Dwarf lionfish
Smaller hawkfish (like flame hawk, others)
Angler fish (best for species only)
Dwarf angelfish (coral beauty is a good one)
Some of the pseudochromids are small, feisty and colorful
Some of the smaller scorpionfish (I have Hawaiian leaf fish and waspfish)
Wrasses - plenty of small, colorful, feisty ones (I like six-line)
Royal gramma - peaceful and colorful, but plucky
Damsels - not my favorite, but they are colorful, cheap and aggressive
Filefish - a trigger won't fit, but there are some nice files that stay small
Sharpnose puffers - stay small, some are very colorful
This would also make an awesome seahorse tank.
2. Equipment. This is where I'm totally lost. I know the equipment involved in a reef, but how much of that knowledge carries over to fish only tanks?
Reefkeeping is all about maintaining good water quality. If you have that down, you should be golden with a FOWLR. The cleaner your equipment can keep the water, the healthier your fish and the less maintenance you will have to do. You don't have to worry about reef supplements in a FOWLR, but do keep an okay skimmer on the tank. Do partial water changes on a regular schedule and keep up with water quality. I'd have at least 1.5-2 lbs live rock per gallon. Lighting is only important for seeing the fish and growing whatever photosynthetic organisms you want (e.g., macroalgae, coralline algae, hardy soft corals and polyps, etc.). I think a FOWLR is enhanced with a few hardy corals and some macroalgae. It takes almost no effort to keep the hardier polyps and mushrooms healthy, and most fish won't touch them. I have power compact fluorescents on most of my FOWLR tanks.
This is my 55 gallon set-up:
BakPak protein skimmer
HOT Aquafuge refugium, lit 24/7 (full of chaeto)
Coralife 4 x 65-watt PC fluorescent fixture
Power filter (forget what it is, but it is a pretty big one)
~75 lbs live rock
2 inch shallow sand bed
several species of red and green macro
polyps, mushrooms, leather corals, Turbinaria
Stock:
-green wolf eel blenny
-pair of waspfish (very venomous)
-small blue spot rabbitfish (venomous) - growing up for larger tank
-small Niger triggerfish - growing up for larger tank
-small angler - must be moved soon, as it is growing fast (should be in species only tank)
This tank will change - once the angler and trigger are out, I'll add back my pair of Hawaiian leaf fish, maybe add another oddball small scorp, like a stingfish or a sea goblin.
Along with the tank a got a free 20 gallon long which I already built a fuge out of to hold more live rock, macro algae, and the skimmer. Do refugiums even have their place in fish only tanks?
DEFINITELY! Refugiums lit either on reverse cycle or 24/7 with macro are great filters and contribute a lot to the stability and health of a tank. You are using nutrient export to keep your water quality up. The plants take up phosphates and nitrates, when you prune/discard excess growth, you are exporting nutrients from your tank.
Besides live rock, and skimmer what type of filtration do i need?
I'd keep the refugium, and maybe keep some surface flow with a HOT power filter. This gives you the option to use chemical filtration if/when needed and helps keep the water well aerated. I usually run mine empty, but will add Purigen, or charcoal, or phosphate remover, whatever, if I need it.
