I would suggest checking for used stuff, you can get a used setup for alot cheaper than new once you factor in the tank, stand and sump you also need to consider drilling, return pump plus the time and fussing with plumbing. Spend half the money and get a system ready to add rock and water without the headache. Also a cheaper way to get your equipment (powerheads, skimmers, lights) plus its way cheaper to get the live rock. I'm guessing your price in pounds means your in the UK, well over in Canada browsing forums I was able to get my skimmer at about 1/3 the price of new. Rock generally goes for 1/4-1/2 the price of in the store. For the price I paid for my tank (reef ready 90g) I could have bought a complete setup ready for rock and water. I had to spend another couple hundred bucks for a return pump and plumbing, would have been more if I hadn't used my 55g as a sump (a sump will generally run another 200 bucks) so like I said if your up for it check out online on local forums or classifieds and you can save a heap. Also remember that provided a tank doesn't have tempered glass it can always be drilled which can save you more. Just my 2 cents