mine takes about 15 minutes to empty a good quarter of the water out of my 400 litre tank. Will depend a little bit on your water pressure I guess.
I got mine and found that the connections are for american 'faucets' rather than british 'taps'. Had to adapt it with a garden hose fitting. cant remember exactly how now but mine now fits straight onto the outside tap via a 'hozelock' style of fitting.
basic operation:
fit to tap and set to syphon. water from tap will pour straight through the fitting and down the drain!!! Not good if you have a large tank and/or a water meter (or are an enviromentalist)
suction is created by the water rushing through the fitting and you can now syphon your gravel.
When gravel is clean/enough water is removed, turn valve around to the fill setting. Cold tap water is then sent up the pipe into the tank.
Add dechlorinator as the water enters the tank.
Job done.
I also add a kettle or two of boiled water slowly as I am refilling to avoid a really big temp drop. obvoiusly this is not added near any fish and is distributed into the cold stream of water coming in.
I also do not have the filter on (my water level is too low anyway) and I add the cold untreated water at the far end to the filter to avoid getting excess amounts in the filter.
if you've got a large tank - get one. Get a long one too - better to overestimate.
HTH
cava
