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

First of all, conclusion: everything is ok, and only ok, just a passable 3 stars. This can work well if you spend a lot of time making sure the pump is actually pumping the right amount of liquid. Because for me the error rate for the application is a bit high. Now the reason, good, "good" and "bad". Good: The price is not excessive for a device that does what it says on the tin and it pumps nutrients, or coral food, etc. OK/I can live with that: the instructions are clearly translated from Chinese, so for those of you who it may be surprised by the broken english in the manual, my recommendation is to read it several times. Eventually you will get it. Or watch online videos from other people who set it up. Poor/or I would say less than perfect: The pump is NOT accurate by any stretch of the imagination. The margin of error, even when set up correctly with the correct rotation ratio of 100ml/k etc, is between 10% and 15%, which can be problematic when trying to pump fertilizer into a tank under 100 gallons. You will either under-fertilize or sometimes over-fertilize the water column. I'll keep playing with this to see if I can find the perfect pumping ratio. But I used a measuring cup to measure 100ml accurately/to calibrate the pump - but every time I ran some pump tests the pump either underdelivered by 10-15% or overdelivered by the same amount. It's worrying. Once, for some reason, one of the pump heads was pumping 2x/200% of the volume while checking the settings 3 times.