Python questions - HELP

[earhtmother]

1) Is there anyway to clean the black coating (I'm assuming it's mold) off the inside of Python tubing? Doesn't *seem* to be affecting tanks but......
2) Python is attached to basement tap & I am trying to clean gravel/WC a 125g on the 2nd floor. I had *assumed* the height difference between floors would make this easier than tanks on the same level I was wrong. I remember being able to get it to work but apparently I've forgotten the trick to it because the suction diminished to nothing barely 10 gallons in this time. So what am I doing wrong? Should the majority of the tubing be downstairs or upstairs? Do I need to keep it *sloping*? Im SO confused

 

[mbkemp]

Is it plugged? I have to play with mine at times to ensure it dies not have debris interrupting the Venturi

 

[earhtmother]

Yeah I had checked over the 50' of tubing end to end several times, taken both ends off checked venturi and found nothing. For some reason forgot the venturi came apart until I was about to give it up as a lost cause when I suddenly remembered taking it apart months ago. Sure enough a **** MTS was blocking the exit where the water came in from the hose at the inner end. Couple of forceful taps & it fell out. Now if I could only magically make all the MTS disappear it would be awesome

 

[mbkemp]

Assassin snail will take care of that

 

[earhtmother]

Got lots of those in my other tanks but for some reason never thought of putting them in here, although since the shells still hang around doesn't really solve the blockage issue