A mini mute submersible pump can be used for computer cooling water circulation or other recycling water place works on 3V with 0.18A with the load and 0.81W on 4.5V. 

Model: JT-DC3W 
1. Rated voltage: DC3V or 4.5V 
2. The use of voltage is best not to overpressure. 
3. No load rated current: 0.05A or less 
4. No load of water ejection capacity: 100L / H 
5. Head: 3V specifications head 0.35 meters, 4.5V specifications head 0.5 meters 
6. Load rated current: 0.18A 
7. Noise: 40dB MAX (background noise 35dB, 0.5M or less) 
8. Power: 0.18 * 4.5 = 0.81W
9. Water temperature: -20 ° C ~ 50 ° C 
10. Environmental humidity: 45% to 90% 
11. Motor; brush motor 
12. Power cord length of about: 20 cm