Hi Drac, welcome to TRT!
I would recommend against adding any animals or microalgae to your tank at this time if you are converting to reef.
The primary thing at this time would be to reorient your setup as a stable platform for the corals you will add later.
The first two components would be live rock and sand. I would recommend pulling the substrate and replacing it with a deep sandbed of 4-6" mix of mostly oolitic aragonite sand with some coarser grains mixed in. See these references:
http://www.reefkeepers.org/faq/cache/33.html http://www.reefs.org/library/talklog...ek_090698.html
You will need approximately 45~70 lbs live rock to establish the heart of your
biological filter along with the sand bed. It can take up to a year for this system to be fully established so patience is essential.
You will need to upgrade your lights. There are many choices here and will ultimately depend on the type of corals you decide to keep. I like VHO lighting and have an IceCap 660 ballast which will drive up to 4 110w tubes. If you should later decide to keep the more
light demanding corals, you could add metal halides later. Many prefer power compact lighting so there are many choices to make in lighting.
Here are a couple of articles that may help:
http://www.thekrib.com/Lights/index.html http://saltaquarium.about.com/pets/s...=2807&cob=home
You will need a good protein skimmer in place of the wet/dry filter. You can use the filter you have but it will be redundant with the live sand/live rock/skimmer. There are many skimmer choices as well, both hang on and sump models should you use a sump. A sump is beneficial as it gives extra water volume and provides a place out of sight for your heaters, skimmer and other equipment. Here is good info about sumps:
http://www.reefcentral.com/northernreef/sumps101.htm
You do have a fairly heavy fish bioload so that your tank needs a good biosystem to keep the water quality high for corals. You might also consider moving the fish into a temporary tank while you replace your substrate and add the live rock.
A clean up crew of snails will be important for algae and detritus control. Here is a great article by Dr. Ron Shimek on snails:
http://www.animalnetwork.com/fish/li...=&RecordNo=166
If you don't already have them, I would highly recommend reading The Conscientious Marine Aquarist by Robert Fenner or Natural Reef Aquariums by John Tullock, or both. You can get both books online for around $50 which would be money well spent. I would recommend reading one or both before doing any more changes to your tank. Remember in your reading that many experts and hobbyists often disagree and reading as many opinions as possible makes it easier to make your own choices. Here is a list of FAQ's that might be helpful:
http://nav.webring.yahoo.com/hub?ring=reeffaq&list
A successful reef tank is a fantastic endeavor but will require time and $$$!
We will be more than glad to help.
Dick
