This is not a question that is easily answered, and as you get more responces I sure you will become even more confused. I feel it really depends on many factors. 1 how much you are willing to spend. If you want SPS I would sugest running halides, and if your tank is 36 inches wide I would suggest 2 of them spaced evenly. The rule of thumb is one every 24 inches but since your tank is only 36 inches running just one may create shadow areas on the side of tank. If you run halides on a tank this small be prepared for high tank temps. and do what you can to avoid that. May mean running an open canopy or haning pendant, not always the prettiest set up buy may help, also running fans over waters surface which will speed up evaporation may help. Worst case you may have to buy a chiller$. I would look in running PC if you are not prepaired for to spend the time and money that may be associated with Halides. PC's are a great lighting solution for people that really want the freedom of keeping corals and do not want to deal with high tank temps. They do not generate as much heat and you can run a close canopy. The draw back is you will not really be able, in my opion, to sucessfully keep SPS. I know this comment will get people going, as I know there are people on this site and other sites that will attest to sucessfully keeping sps's under PC's. I think it comes down to what you want to keep and what you are willing to spend. By the way Halides have really come down in price and I have seen complete systems for less than standard PC's.
