Assuming your trainer is in good working order, Cycleops Fluid2 is a supported Classic trainer and should have reasonably accurate zPower. Did you:

• Tension knob, tightened to mfr. recommendations?
• ....and tire not slipping?
• 700x23 tire with mfr recommended psi? generally 100-110 psi
• Ant+ dongle close enough to your speed/cadence sensors? Sometimes you need to use a USB extension.

Doing all of the above you should get a somewhat reasonable power reading - yes it won't be as accurate as a Power Meter or Smart Trainer, but also shouldn't be completely off the charts especially at low-mid efforts on power curve.
...or unless you're the Hulk or something, then maybe 700w is accurate after all