Review on Jebao Programmable Auto Dosing Pump DP-4: Efficient and Flexible Black Dosing Pump by David Guerrero

I think the pump is excellent. But only 4 stars because of that. The instructions ensure that each pump is calibrated using water as the calibration solution. Eh wrong answer. Let's say pump 1 is solution 1 and pump 4 is solution 4 (same for 2 and 3). Good. For each of your solutions, you have a different solution viscosity (thickness of the solution relative to the solids dissolved in the solution). This means if solution 1 has a different viscosity level than solutions 2-4 then you cannot just calibrate the pumps with the same water solution. Which have the same viscosity at each engine calibration. What I'm trying to say is for me (freshwater aquarium with plants). Solution 1 - Excel, 2 - Macros, 3 - Micro and 4 - Hardware. I had to line up solution containers and specify the length of the tubes (the tubes hold a volume of liquid). First vent the hoses manually and then start the calibration again. And then you can calibrate each motor head based on the measurement of a 100ml graduated cylinder. It is very cumbersome to properly calibrate each head. I don't think it's different from other brands. Second failure on this pump. Let's say on Monday I set my pump time to 12pm, which is the time on my phone. Until next week Monday my phone says 12 noon but the pump will be 12:03 noon. This means there is definitely a lack of timing accuracy on this processor board. Aside from needing to adjust the timing about once a week and being carefully calibrated, this pump is a great deal for what you get. They give you an extra motor head, let's see if I need to use that spare head. I hope not but will update if I have any issues with this product.