Bud in my opinon 1.8 wpg is barely enough for a softy tank. Heck my 7g nano has 9wpg. You will be seriously limited to what you can keep like GSP, clove polyps, xenia, kenyan branching, zoas and mushrooms. It would be difficult to claim a 30g reef tank without some nice specimens of lps or sps. At least consider an Odyssea fixture from my friend matt, www. thehobbypalace.com I have a nice 130w PC fixture over a 20g planted that might pull it off for you. My friend uses the same fixture with one 12k bulb and one 20k bulb over a 20g reef. He can't grow SPS nor can he keep a clam but he has a few LPS like torches, frogspawn and hammers.
One note about lighting. It is the single most important thing about your reef tank besides clean water. It isn't important in any other tank besides a freshwater planted tank. Proper lighting is what makes your coral grow and what keeps it alive. Most coral is photosynthetic meaning it lives from the light you provide. So I cannot stress enough that there is no such thing as to expensive lighting. If you shop around you'll be pleasantly surprised. I can turn up used fully running 150w pendants for about $80 all the time. that really is not super expensive. Also a little 150w pendant will not eat up your electric bill. think about it, you should be thinking of at least 210w to fully support a nice SPS or clam collection. 200w running 8 hours is only 1,600w or 1.6kilowatt hours. Around here a kilowatt runs about 10 cents. So your 150w halide would cost about 15 cents a day to run. or about $5 a month. PM me and I'll link you to a calculator that will estimate the entire cost of your tank for you, you can show that to your mom. I won't link from the site as it is to another site and I noticed admin doesn't approve of that.
I'll even offer to help you find a reasonably priced pendant.
Never buy undersized lighting. As your tank matures and your interests change you will only be limited by your lighting demands. Why pay twice or threee times when you can get it right the first time? I started out with flouros, trashed em. Traded up for a 2x 150w MHQI 2x 200w PC fixture. It seemed great for about 6 months. I then got frags from a friend that died. He came by and laughed at my lighting. I went ahead and bought another system, 1000w total. Now everythign is awesome. That is on a 75g. I would have had $800 to spend on corals and fish had I not wasted my time buying underpowered lights.