New Tank

I do use a normal chopping board and knife for bloodworm. It's certainly no worse than chopping chicken.
I don't use my cheeseboard though, it being wooden and not so easy to wash. But wood does have it's own antibacterial properties.
I'm trying to work out what you mean Pawel, think I see, might try it.

Here are two simple ways of starting a syphon without getting tank water in your mouth.

Method 1

• Take the end of the tube you are using and mark off a point about 1 ¹/₂ to 2 times the depth of your tank from the end.
• Make sure the tube is open and free from instruction.
• Feed the tank end of the tube into the tank making sure that it doesn't curl round and poke above the surface.
• Keep feeding the tube into your tank until you reach the mark you made earlier.
• When the marked length is below water level, seal the bucket end with your finger or a cork or a clamp or something.
• Place the bucket end in the bucket. 
• Withdraw the tube from your tank until the marked bit is below the open end in your tank.
• Remove the Finger/Clamp and the siphon will start

It doesn't matter whether the tube is 2m long or 200m.

Method 2
I use this one all the time for emptying my tank by (20m) hose pipe.

• Lay-out the hose as it will be when the siphon is active. Tank end should be secured in some way, especially if it's out of sight of the other end, in my case in the bathroom.
• Make sure that the hose immediately upon exiting from the tank, runs down below the level of the tank.
• When ready, suck on the open end. You need to suck enough to fill the tank end from the start of the hose to the point where the hose runs below tank-level.
• When you have sucked enough, the siphon will start and fill the rest of the hose for you. I find two mouthfuls is plenty.

OK, does anyone else use the cheese knife and board for chopping up frozen bloodworm blocks? (Thought not )

Yes actually, although I use the veg knife 

I ALWAYS start mine off by sucking it through and spitting the mouthful I get into the bucket I'm syphoning into.  The water looks so clean, I kid myself it's safe, lol.  AND I use my veg knife to chop up the frozen bloodworms on my regular chopping board.     I'm of the belief that the more "dirt" you eat, the more healthy you are..... it's worked so far 

I'm a nurse and have built up quite a good resistance to buglies over the years but no way would I suck a fish tank water into my mouth..lmao! Have you seen the poop that comes out of a good gravel cleaning session?   

I seriously hope you brush your teeth and gargle with a flippin good anti-septic mouth wash before you kiss the missus