He said a gate close to 3,000 would make all the difference though as the players would react to a loud crowd getting behind them.
After Peterborough were promoted to the National League North in 2022, Hereford were beaten 1-0 at home last August as injuries plagued Caddis's side but they recorded a revengeful and convincing 4-1 away win in March.
It was a similar picture the previous season, with a 1-0 defeat at home and a 2-0 win away towards the end of the season.
The Turbines will be searching for their first win of the season, having lost 1-0 at home to Chorley and away at Warrington Town.
After Saturday's 1-1 draw at Chorley, Caddis admitted it would be a tough game, saying his side had "a couple of poor moments" in last year's home defeat.
He said: "I think they'll be physical [Peterborough Sports]. They'll be up for it. They're coming to our stadium and they're going to come and try and spoil the game and make it tough for us, so we've got to respect them, but we've got to put our own imprint on the game and we would love for the place to be rocking.
"I know it's a Tuesday night, we're obviously hoping that the kids are still off school and we can get as many as we can.
"It's games like Tuesday night when we're playing Peterborough Sports, they're the ones that we really, really need supporters to get behind us. We understand it's difficult, we understand financially it's difficult. Kids are still off school, as I said.
"Kids want to do all sorts of other stuff, soft plays and all the rest. I absolutely understand that, I've got two kids of my own, but if we can find a way of getting the place bouncing and if we can get, two-and-a-half, three [thousand], whatever it is, then we'd really appreciate it and the players will react to it."
Kick off is at 7.45pm and tickets are on sale via the club's website.