Polytunnel watering system

Hi, new member here. This is my first question.
I have a 30' x 14' tunnel and it is in its third season so I am still learning. The tunnel is behind a sheep shed so the water supply is from the 1200 sq ft shed roof which is collected in an IBC and I have a pipe and tap from that. There is no possibility of an electricity supply to the tunnel. In my first season I installed a leaky hose watering system from 2 barrels inside the end of the tunnel which are up on 18" blocks. I used battery operated timers - the only timers that I could find to work on low pressure. It worked swimmingly for a few days then I wasn't sure about the timing so I kept upping the watering times. Eventually I forgot the timers and just left it run for the day but the water in the barrels was going down so slowly it can hardly have been working and I could tell that the hose hadn't been wet so I gave up using it.
At the end of the season I opened the stops on the ends of the hose and the barrel taps to empty the remaining water from the barrels and hey presto, immediately the leaky hose started leaking like a good'n all the way along its length! I took the hose up for the winter and just haven't had the incentive to put it all back down and try again.

My only thought so far was that once the hose got wet the holes got clogged by particles in the water and prevented the hose from working but that after I had stopped using it and it had dried out thoroughly the holes returned. I have no idea. Does anyone have any experience of leaky hose or any other watering system?
A couple of pics of what I did.

 

I did speak with a giant pumpkin grower via email a few years ago about this very subject, he was starting to have the same or similar issue with leaky hoses blocking up after a few seasons use. Even dragging the hoses over soil carefully to lay them out results in them getting dirty, leading to clogging, walking up and down a dusty path like in your pic above will again add more dirt to the hose.

In the end we reasoned that using some old curtains or similar, cut into strips then sown into a giant covering sock would be the way to go in the future, keeping leaky hose clean. They can be removed and washed end of season keeping everything nice. I lost contact with him so I do not know if it worked or if indeed he ever tried it.

Steve...

 

Thanks Steve. That's not very satisfactory (I mean the hose, not your reply) as its not really up to the job it's supposed to do. I've seen it recommended that the hose is buried - I'm not sure I can see that being any different.
I don't know if I can face constructing 150' of sock and threading pipe through it as an experiment. Having 2 seasons under my belt now I've actually not found watering with a can too difficult as the clay base to the beds holds moisture very effectively. Even in the last month of very hot weather (almost unheard of here), with the temperature in excess of 40° in the tunnel, I haven't had to water every day and nothing has suffered.

 

The leaky hose I've got is 'proper soaker hose' afaik. I don't have access to mains water for the tunnel - it's nearly 1/4 mile away. I have thought about trying to filter the water as it goes into the barrels using a milk sock, I might give it a go one day but I would presumably need to clean the hose first. On the other hand I might just forget it and stick with the watering can.

 

I actually first started my toms and other stuff in rings, bottomless pots and miscellaneous bits of redundant drainage equipment because when I did the beds I didn't have enough decent topsoil to put on top of the clay. As I've emptied out the pots each time it has added to the topsoil layer of the beds and I am starting to get some presentable soil. I also have the advantage of a massive muck heap complete with a healthy worm population right next to the tunnel. I also find the rings help to target the watering rather than it running off onto the paths and other places I don't want it.

A problem I do have JWK is that we don't have mains water for the house either (intending to change that) and our water pressure is very low. We have to have a pump to get half decent pressure in the house. The leaky hose worked just fine for the very short time it was actually working - that is in terms of the water reaching right down to the end of the tunnel on all 5 lines. When I opened the taps on the ends of the lines there was a reasonable flow of water coming out. I'm sure it was just the clogging that was the issue.