Oh dear, must be a day for externals and wet floors 
Done water change/filter clean on 1 tank, fine :)
Waterchange and filter clean on 4footer, took lid off external, picked the body up to empty and rug slipped on laminate floor, about 1/3rd of the water flew out on the rug and laminate. Quick fly about with towels to mop up 
3rd tank, waterchange and ext filter clean no probs
THEN I had the bright idea of setting the wet/dry 2229 filter on it as 2nd filter 
Set it all up, , it filled then drained and stopped, didnt refil again so mucked about with pipe heights etc. Started it off again, didnt drain but it should and after afew mins i heard a kind of "pressure/strain" noise. I thought, hmm, ooohh don't sound right then i noticed it was leaking from the float valve coupling in the middle
PANIC AGAIN !!!!!!! Run about with another towl mopping up and i tried to nip the coupling but more water came out so switched off and still leaked!!!!!!
I closed the valves (so i thought) and clicked the release and took pipe head out, forgot i'd just turned 1 tap off, not both, more water on floor 
I've just dumped the filter in the bath and not even touching it until tomorrow or I might just smash it!! going to have to pop into the barbers below in the morning to see if any water has went through the ceiling 
I want a ground floor flat with concrete floors lol