How to set up a drip irrigation system?

[hetas]

Hi, I have just joined this platform and it is an amazing find. 

Last month, I installed a drip irrigation system at our weekender land near Kingaroy. However, it looks like I have messed up something. Even when my rainwater tank is going down drastically every week, whenever I check the raised beds, they look dry. Though the plants are surviving so not complaining about that. This was my first time doing anything of this sort. So please be kind if I have made some stupid mistakes.  

Here is the image attached to give some idea and context. 

Some specifics are below: 

1. Rainwater tank: We have a 22k litre tank which is about half empty now. 

2. Pump: I am using 12v, Ozito water pump that delivers about 600L per hour/10L per minute water. We don't have power onsite so using 12V battery and a solar panel. However, I can upgrade the pump if required. 

3. 13mm Polypipe: I didn't know that I should use 19mm initially and later 13mm. So I used all 13mm from the rainwater tank to pump to raised beds. 

4. 13mm drip irrigation pipe: Each bed is 3x1.5m in size and is 420mm high. So we spread about 21m of drip irrigation pipe on each bed (total 10 beds x 21m = 210m) in spiral motion to avoid putting a lot joints . Read somewhere that each join reduces the pressure. 

5. Each bed has 13mm barbed tap at the start. 

6. Automatic timer: I have GARDENA Flex Water Computer to water the beds every 48 hours for 40 minutes. 

7. From the pump to the beds, there is an elevation of about 2 to 3m. So the beds are sitting higher than the pump. 

Is this overkill/underkill? Do I need to upgrade the pump? Should I replace the initial run of 13mm poly pipe with 19mm or higher? Should I upgrade the pump? How much water roughly should I need every month looking at the current setup? Based on @Adam_W YouTube video, I can now understand that my pump is able to push 10L per minute, which is 400L each time my timer turns on for 40mins every 48 hours. 

But then the drip irrigation pipe can drip about 5.3L every hour per meter and looking at my current setup, I have about 200m length of drip irrigation pipe layed. So that comes up to be around 750L every 48 hours. Do I need to increase watering? Or decrease? 
We are getting bore drilled in a month's time but right now rainwater tank is all we have got. 

PS: We don't live there full-time. We visit every weekend and don't use water too much as we have composting toilet and no shower facilities currently. So this question is more about setting up right amount of water for the raised beds. 

[J-P]

@hetas @tanveersattar @EricL - but wifey doesn’t believe that drip irrigation is enough to keep the plants healthy. Finally gave up and switched to jet spray to show visible watering.