Switched my 60L air pump off recently and left it for a while before switching it back on. I've been toying with running air and skimmer only 12 out of 24hrs to try and cut down on the bills!
Normally it's not a problem, but today I've found that water must have worked it's way back up the air line and the pump doesn't seem to be able to push it back into the pond. So I'm left with an aerated BD, but no way of getting air into it. In the past I've had water come out of the air line when disconnecting it, but it's always worked ok when plugging it back onto the pump. So do you think this is the pump getting weak? Does anyone else have or had a problem like this.
In anticipation..........
hi louie
i will go first.
Not sure about pump could be a little less pressure coming from it.
My suggestion would be based on how long your air line is.If not too far away why not give it a good blow with your mouth.The other would be have you or can you borrow a air compression and blow the water back that way.
darren
Can you find a friend who has a bigger pump? Connect up, blast through, then quickly swap your pump back again. Sorted.
Chris (another one)
Oh yes, and next year, when the water warms up a bit, get in the pond and fit a non-return valve in the air line, as close to the drain as you can, so it`ll never happen again.
ageinghippy wrote:Can you find a friend who has a bigger pump? Connect up, blast through, then quickly swap your pump back again. Sorted.
Chris (another one)
Oh yes, and next year, when the water warms up a bit, get in the pond and fit a non-return valve in the air line, as close to the drain as you can, so it`ll never happen again.
That's a damn good point there! I don't remember ever seeing a recommendation that you should fit a non return valve in the air line as close to the BD as possible. Even if I did put one in now it would still be 4 feet above the BD at the closest point. That's where the air pipe comes up out of the concrete. That's one for the pond builder's book!! Wish I'd thought of that when I did the build.............(Along with the other150 things!)
Chris I see your point and the lower market air pumps will always struggle to give acceptable results. However if once topping up you run the air pump on the BD you should never get water comong back down the airline as the one wat valve will stop the return making it easier for your pump to carry on and do its job.
A car foot pump along with a little perseverance and some insulating tape finally got the line clear of water. I won't be taking it off again until I've got an 8mm non-return valve in my hand!
when you fit your non-return valve make sure you clamp the pipe first so the water does not travel back up the pipe, once youve got the valve in place you can take off the clamp
The cause of water in teh air line is one of two things, either
condensation from the warm air leaving the pump cooling before exiting the drain, or the membrane on the drain has strtched a little or has a slight tear in it whcih is letting water back.
I would of borrowed/used apond vac to suck the water out, this would have given the answer to the above, if you emptied the line and it became dry then its either a condensation or a strectched membrane , if you got constant flow of water then the membrane has split.
I don't remember ever seeing a recommendation that you should fit a non return valve in the air line as close to the BD as possible. Even if I did put one in now it would still be 4 feet above the BD at the closest point. That's where the air pipe comes up out of the concrete. That's one for the pond builder's book!! Wish I'd thought of that when I did the build.............(Along with the other150 things!) 
