Hi Jen,
Sorry it's taken me so long to reply, been working hard! In answer to your questions above:
1. I'd go with the aqua c remora nano, heard very good things about this skimmer.
2. I think 72 watts (3 watts per gallon on a 24g) would be fine for what you're planning but you'd need more for lps. One tip, actinic bulbs are nice for getting a nice blue hue to the tank but don't actually emit much useful light. It might be worth putting two 12k bulbs in the main fitting and adding one of these (
http://cgi.ebay.com/LED-Double-Aqua...ryZ46314QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) off ebay to get the blue shade. The difference between mh and hqi is basically that mh gives you more bang for the buck. It's better at penetrating the water to greater depths because it's more intense. The problem with mh on a nano is heat control because they give out a lot of heat.
3. I like the koralia nanos because they have a nice wide flow distribution so don't blow the hell out of one area. The tunze nano stream is a good powerhead and a small maxijet (300) would do the job. This is something you'll have to play with once set up.
4. It's generally recommended to have 1-2 lbs per gallon but I'd go more for the 1lb per gallon otherwise you're likely to overfill a nano and leave no swimming space. Also if you add corals later on you'll be adding them on liverock so you need to leave space. I'm in England so not sure what a good price would be sorry but from what I've read on here around $8-10 per pound is average. I wouldn't do a deep sand bed in a nano (not enough room) so I'd shoot for somewhere between 1 and 2 inches deep. Seeding the new tank with sand from yours is a good idea, should make the cycle a bit quicker. You will need to cure the live rock, this is because even with cured live rock there will be a small amount of die off during shipping. This die off causes a small peak in ammonia so it needs to be cured before putting any fish in. I would start the new tank up while keeping the old one running. Put the sand (along with some from your old tank) and live rock in the new tank and get all the filters, powerheads, lights etc running. Test the water every day until you have 0 ammonia and 0 nitrites and the nitrates have come back down below 20ppm. You can do regular water changes during this time to keep the ammonia low and avoid excess die off on the live rock. Once the parameters are correct, I'd put the clean up crew (snails, hermits etc) in there and give it a few days to stabilise then add the Fire Shrimp and the clowns at the same time making sure to acclimate them to the new tank. If you wanna add anything else I would wait minimum a week after adding the clowns and test parameters before adding. Live rock in the filter is better as the bio-balls can trap detritus and become a nitrate factory. Either way you will need to keep the filter well maintained. To be honest with 1lb per gallon liverock you don't need any other biological filtration so it might be worth using the filter for chemical filtration (carbon, purigen, rowaphos etc), especially with corals.
Hope that helps, Matt.
