I have been using the Python for nearly 20 years. Hook it to the sink a just water temp on tap, turn valve to fill. Now close valve at the vacuum end in tank, leaving the vacuum in the tank i disconnect the hose from sink and set it out in garden. Come back to tank and open valve at top of vacuum tube. I found the water moves much quicker this way especially if you want to vacuum and I can hook up another fill line and be filling at the same time. This one item saves so much time and effort it is well worth the $50 i put out. I have since bought other attachments and valves. IMO
it is a must have, right up there with the filter or heater. Get one you will be glad you did. Makes water changes a breeze.
Point to remember when using the vacuum system, it will suck up fish so you want to have a valve at the vacuum head. I do not vacuum much as it causes upsets to the Eco system is what I found. So I put net material over the intake end and put the vacuum down against the gravel and use a C clamp ( plastic one ) to clamp it in place on top of glass. Also clamp the fill line or it will slip out and be on the floor.
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