Auto Dosing EI (Estimative Index) With Jebao / Jecod DP Series (DP-3) The DP series of peristaltic pumps by Jebao / Jecod offer a cheap and reliable way of automatically dosing pre mixed Estimative Index (EI) fertilisers to your tank. There are various offerings in the series, the number at the end denoting how many different pumps are included (2, 3 or 4) If you only intent to auto dose EI, then the DP-2 will do fine. The best price at the time of writing delivered was £48 delivered from Hong Kong. I ordered the DP-3 as I want to auto dose water conditioner too, which was £54 new from Hong Kong on eBay. These pumps are available in the UK too, the DP-3 I've seen for £72. Given mine arrived in 3 days, I'd recommend the HK option! Set Up Time / Date For EI Dosing Firstly you will need to set the correct time / date on the dosing unit. When plugging the unit it the first screen you will see if this - this is the "Home Screen"... The middle button I refer to as "OK", which you will to press to get into this menu... Pressing OK again takes you to the screen to set the time / date. Simply use the left / right arrows to toggle between date / hours / mins, and the up / down arrows to change these values. OK again saves the new time / date. Priming & Calibrating The Pump Set the pump up as you intend to use it. The left side tube of the channel is the intake (to go onto your mixture), and the right side goes into the tank. For this part you may wish to flow into something else whilst you test. Press either the left or right arrow, select the pump, and hold "OK" until the mixture is drawn all the way and no air bubbles remain. Once this done, you are now primed. Do this for both channels. Press ESC once done. Next is to calibrate the pump. You will need to 100ml measured out into a container for this part, an the intake tube into this. Press either the Up / Down arrow, select the pump, then press OK. As soon as 100ml is taken from the container, press the Up Arrow, then OK. Once this done, you are now calibrated. Do this for both channels. Press ESC once done. Settings For EI Dosing This pump does not easily allow you to set up different alternate days for each channel, nor the rest day on Day 7 as usually needed for EI. What we can do is "bodge" an acceptable compromise. The pump is set up to dose at *about* midnight every day. This is done by dosing twice every other day (23hrs 58mins apart). The down sides are firstly you end up on a 'two week time table', so dose Mon, Wed, Fri & Sun in week 1, then Tues, Thurs & Sat week 2 - which is not really an issue. You also end up wasting an extra dose on water change day, which is around 19p on my 400l tank I'm told. Dosing schedule ends up looking like this... Mon - Macro @ 00:01 (Ready For 'Lights On' Monday) Mon - Micro @ 23:59 (Ready For 'Lights On' Tuesday) Wed - Macro @ 00:01 (Ready For 'Lights On' Wednesday) Wed - Micro @ 23:59 (Ready For 'Lights On' Thursday) Fri - Macro @ 00:01 (Ready For 'Lights On' Friday) Fri - Micro @ 23:59 (Ready For 'Lights On' Saturday) Sun - Macro @ 00:01 (Ready For 'Lights On' Sunday) Sun - Micro @ 23:59 (Ready For 'Lights On' Monday) Tue- Macro @ 00:01 (Ready For 'Lights On' Tuesday) Tue- Micro @ 23:59 (Ready For 'Lights On' Wednesday) Thur- Macro @ 00:01 (Ready For 'Lights On' Thursday) Thur- Micro @ 23:59 (Ready For 'Lights On' Friday) Sat - Macro @ 00:01 (Ready For 'Lights On' Saturday) Sat - Micro @ 23:59 (Ready For 'Lights On' Sunday) To set this up, start from the Main Menu... Press OK, select Set Program and select Pump 1... Pump 1 is set for once per day, then press OK ... Pump 1 is set for an interval of 1 day (ie, every other day), then press OK... Pump 1 is set for your required dose (90ml in my case), then press OK... Pump 1 is set for 23:59, then press OK... Pump 2 is set as per Pump 1, but with a time of 00:01... Conclusion That is all there is to it really. For the first few days have the pump put the mixture into a separate container so you can monitor what it is doing. Once you are happy it is all working as it should, you can then direct it straight into the tank or sump. All you need to do now is keep an eye on your containers to ensure they are not empty and ensure your intake tube remains at the bottom of the storage container (you may wish to weigh it down). Hope that helps - any questions / corrections / thoughts please post below!