plumbing question

[pirate]

Well I finally got around to drillin my tank yesterday and now I'm lookng for everything else. I drilled it for 3/4 bulkhead ( because I had them) . I have found some 1 inch pond hose (black). I quess really can I use it instead of rigid tubing? I drilled the tank for a herbie type overflow, will it cause a problem the different sizes? (like noise etc) Or is it better to make everthing the same 3/4 out and 3/4 in?
Thanks