Can you post a picture of your consumer unit just so i can see if you have an RCD protecting the socket circuits.
An FCU is that switch you have above the double socket which the cable from outside goes into. Basically its a switch with a fuse to protect the outgoing cable, this is known as a fused connection unit (FCU), the fuse in it is most probably a 13amp one which isn't providing the correct protection to the pump/filter which should most likely be fused at 3amps, if you changed the fuse to a 3amp this would then restrict what you can plug into the socket as any high powered appliances would cause it to blow.
The hi-tuff being buried isn't really correct, it should be an armoured cable, i just wanted to know how deep it was to see if its at risk of being damaged by a spade, i suppose it depends on how likely you are to start hacking away at your lawn with a spade
As i say its not a dangerous installation but needs tidying up. An easy and not so costly solution would be to remove the socket if you can live without it and just move the switch to a better location, then replace the fuse in the FCU for a 3amp one.
All the best
Dan
An FCU is that switch you have above the double socket which the cable from outside goes into. Basically its a switch with a fuse to protect the outgoing cable, this is known as a fused connection unit (FCU), the fuse in it is most probably a 13amp one which isn't providing the correct protection to the pump/filter which should most likely be fused at 3amps, if you changed the fuse to a 3amp this would then restrict what you can plug into the socket as any high powered appliances would cause it to blow.
The hi-tuff being buried isn't really correct, it should be an armoured cable, i just wanted to know how deep it was to see if its at risk of being damaged by a spade, i suppose it depends on how likely you are to start hacking away at your lawn with a spade
As i say its not a dangerous installation but needs tidying up. An easy and not so costly solution would be to remove the socket if you can live without it and just move the switch to a better location, then replace the fuse in the FCU for a 3amp one.
All the best
Dan