It's good to even isolate the first fish intended to go in there. One of the main reasons is to avoid an ich outbreak in the main system along with anything else. Especially with that big of a tank. From now on...any fish you get should be isolated for a week or two. This will save you a headache or two...
LOL.
How long was the tank without fish when once it was all set up? A couple of weeks? A month? Give me an idea here.
It takes about two weeks for fish to 'settle' into their new homes. During that time it is good to keep a sharp eye on pH and ammonia. If there is a spike in ammonia, naturally pH should drop. If and when that happens, tend to the ammonia first then the pH. The lower pH value during an ammonia spike helps protect the livestock in the system. A lower pH will transform the ammonia to the less toxic form of ammonium. If you tend to the pH first, then you'd be making the system more toxic and increase the chances of fish loss.
Take your time with populating the tank. People want their tanks full of life right away, but that often leads to disappointing failures. Wait at least two weeks in between introductions and only introduce a few at a time except reef hermits and small snails.
Being that the water quality is good, you can do a normal feeding routine. Marine fish should be offered a total of up to 5 minutes worth of food per day. With live rock, you can cut that back to every other day. As the tank matures and the live rock puts on growth, the feeding can be cut back to three times a week. Generally, the live rock will help produce natural food such as algae and copepods.
Food is best fed several times throughout the feeding day instead of one large feed. The fish's body uses more of the food's nutrient value instead of being pooped out so there's less waste.
Give the clowns some time to adjust. Once they are settled and you are ready to add more life to the tank, focus more on the clean up crew. Snails, reef hermits, perhaps an algae/rock blenny as well. I personally like the cerith snails. They are small and can get into the cracks of the rock to clean up algae growth. Astrae (sp?) and turbo snails are good for the glass and larger surfaces of rock. If you are not going to get into corals, some of the larger starfish species can also help control algae. One of the best marine algae grazers are sea urchins, however, they do also eat that nice purple coraline algae, so if you want that, then a sea urchin would not be a good choice. If you don't care about the coraline, then the sea urchin makes an interesting addition.
Don't be afraid to add in a bunch of reef hermits and small snails at once. Say for the first batch you can put in 20 little hermits and about 10 small snails, then add on every so often as needed. You have a large tank and you'll need them. Besides, when populating a tank, it's the fish that put a dent into the bioload more so than inverts and coral. It's so much easier to keep them alive then it is the fish.
Do you plan on housing coral in the tank?
A little hint...if you add on to the substrate till you have a nice deep bed of about 4" and put some critters in there that live and/or crawl through the sand bed, it will help control nitrates and eliminate the need to vaccuum. Still need to do the water changes, but you could ditch the gravel vac!!
Using the deep sand bed will choke the bottom layers of oxygen and allow denitrifying bacteria to cultivate within the system. Things living and crawling through the sand will release trapped gases from the denitrification process which would complete a full bio cycle. I've found it to keep a system much healthier in my experience.
You have a nice tank to play with, but play slowly and have patience. Keep in mind...if you plan on having tangs or angels wait till the tank has been up for at least 6 months for better success of keeping them alive. There are tons of different little inverts you can focus on before hand and lots of other neat little fish that can be housed. If you keep to a simple rule of lesser aggressives in first, you'll avoid most problems with fish being attacked upon introduction. THIS INCLUDES DAMSELS. Damsels are mean. Make them one of the last additions unless they are green or blue chromises. They're not as bad, but most other damsels have a serious attitude and are best kept either single or a small school of five or more of the same species.
Enjoy