Aeroponic clone bucket on/off intervals

I made an aeroponic clone bucket and while my seeds have rooted fast in it, my clone is taking forever. It's day 50 and barely showing roots. It's the most successful clone I've had. The pump/sprinkler runs 24/0 and I'm wondering if it needs to be on 15 minute (or some number) intervals. It would be nice to hear from people who have used this setup.

the main reason I cycle the pump in a cloner is due to heat. run a pump 24/7 and it's gonna generate some heat.
50 days???

It spent the first 21 days in a shot glass. Thanks for telling me about the heat, I'll check it out.

No problem. I'd recommend a Titan Apollo 12 cycle timer, they can be had for around 60 bux. They're adjustable down to 5 seconds on/off.