Spent So Far

Below is an ongoing tally of the cost of a marine start up:

Secondhand Kent Marine Bio Reef 97L Aquarium bought on Gumtree: £100.00
Kent Marine Bio Reef/River Reef 94 Aquarium Cabinet: £52.95
Kent Marine Nano Protein Skimmer £27.50
Kent Marine Skimmer Weir Gate from Interpet: FREE

Kent Marine Bio Reef Pump Impellor from Amazon £8.99
Interpet T5 36 Watt Twin Reef Daylight Lamp from CD Aquatics £15.48
Interpet T5 36 Watt Reef Daylight Blue Lamp from CD Aquatics £15.49
Loc-Line directional hose from eBay £17.99
One meter Eheim tubing for Kent pump from Maidenhead Aquatics £1.99
DD Reverse Osmosis Unit, 50 gallon per day model from Swell UK £79.99
DD Deionising pod with resin from Swell UK £12.34
Maidenhead Aquatics LIVE ROCK @ £7.99 per Kg £79.90
Red Sea Coral Pro salt 7kg  from Swel UK £22.99
DD Refractometer from Swell UK £31.34
Hydor Koralia Nano x 2 from Swell UK 
Salifert Test Kits from Swell UK £52.72
TDS pen bought on ebay £4.99
Magfloat glass cleaner from ebay £11.99


Running Total: £591.86




I think it's fair to say that the expense of a marine tank will be ongoing, so I'm leaving it here as a good indication of what you can expect.