there is a new marine fish and coral fish shop opening in balham in London. at the moment it is only open on weekends, but it is worth a visit. ive started volunteering there, and the owner is very knoledgable and has been showing me the ropes, and although only small at the moment has quite a few fish and lots of coral. its quite out the way, but if anyone wants to go i can post directions. they dont sell tanks, only marine fish and coral.