Seen walking about the historic center of Durham, UK:
Ah, yes. It is a deal where you pay actual money to put your tootsies in a shallow pool, at which point small fish nibble off all the dead skin! Now the logo, a fish and two somewhat wonky looking feet makes sense. As does the groaner of a motto: Bon Appe Feet.
I guess this is a fairly new thing, just starting out as a commercial venture in Japan in 2006. The practice has spread world wide, with the first such "Fish Spas" opening in the US in 2008 and in the UK two years later.
In the brief wikipedia entry on this topic it is noted that: "Before being outlawed in most U.S. states, the novelty of fish pedicures was viewed as a possible revenue enhancer for struggling nail salons, which had experienced less "luxury spending" from their regular clients during the recession."
A degree of economic struggle is hinted at here too, note the location opposite "Poundland" which is the UK equivalent of a dollar store.
While still legal in the UK the Health Protection Agency recently issued an advisory to the effect that it viewed this as a potential risk for the spread of HIV and hepatitis. Apparently there is some possibility of people bleeding when being repeatedly bitten by many small fish, and it is always such a pain to change aquarium water after each client!
The sign looks more than a little droopy. Its probably just the torrential rains that the UK had been having, although I would not rule out a bit of sagging of interest in the concept as a whole.