Help Please got a leak :(

[Dan!]

Is it leaking from the bolt arrowed in the photo below? Thats the only bolt I can think of as a 'triangle bolt'....



If so, the best way I found to loosen/tighten them is by getting a 1/2" imperial socket which is 12 sided (not 6 sided) and then gently hammer it onto the bolt, it should go on fairly easily and will be enough to nip it up, theyre not very tight normally tbh.

Edit, just to clarify incase you dont know....

6 sided socket:



12 sided socket:




Hope that helps