In trying my best not to touch the tank while it is cycling, I did the experiment
Though the 2 pumps weren't exactly identical, they are both rated to run at 1.5V. I did not connect any tubing yet and just see if the motors would run.
Results:
1 motor (the one with the automatic ac sensor), was working perfectly fine, the other 1 was very quiet and was pumping air very lightly.
Conclusion:
These motors would probably not work even the motors came from the same manufacturer.
This myth is busted!
Recommendation:
To be able to use car battery:
- look for a 12V air pump
- use a step down transformer, or car adaptor that have 1.5V
- use the Car's Tyre Compressor/Inflator
OT: I'm installing Crysis game, hope that would help quicken up the tank's cycling