Blessing in disguise

[James WF10]

So the other day before i came to work i had planned on getting the covers on my pond (very late this year as been so busy). I work away a week at a time and didnt end up getting chance to get the covers on, about 4 days into my 7 days away the mrs rang me in a bit of a panic saying the water had all gone out of the pond. When she got outside she saw it still had water in the bottom half (i have a ledge half way down the pond which drops from about 3 foot to 5 foot deep)
Initial thought was that we'd been burgled and had all my filter equipment knicked and felt sheer relief that i fitted CCTV cameras last month
i had the mrs turn off all the equipment and when i got home i did some investigations, my pond has a bottom drain which feeds up and over then into the bottom of a sieve. The fitting into the bottom of the sieve had come off and will have basically drained about 15,000 gallons of water out the pond in about 2 minutes flat, flooding all of the compartment where i house the bead filter and sieve. The rising water had caused my sieve to float up out of its holding and break all of the fittings at the end, took me a good few hours to get everything fitted back into place.
Filled the pond up slowly over about 3 days as i didnt want to put too much freezing cold tap water into it too quickly.
After scratching my head for a good 3 hours due to an air lock in the u-bend from the bottom drain to the sieve, i tested everything and incredibly all was working fine.
I think putting the covers on late this year was a blessing in disguise for me as if the covers were on then i wouldnt have known the water had drained and in all honesty i would have probably waited a couple of weeks before i checked on the pond to make sure everything was looking ok (not something i will be doing in the future, i'll be checking every few days)
I am now planning on making a float with some sort of flag or something on to show that the water level under the covers is ok, reckon a few milk cartons a stick and rag would probably do the trick.
Close call for me and the pond this year.
Cheers
James

[Duncan]

glad it all worked out mate, it would have freaked me

dunc

[Manky Sanke]

James,

I don't think this is pump fed, in which case a float switch would be the ideal solution but, from your description, it would appear that the water syphoned out via the bottom drain pipework going up and over the pond wall. If that's true then easy peasy!

The way to stop a syphon is to let air into the loop above the water level. In your situation, work out the lowest your pond water level goes during filter maintenance and drill a small (3mm ish) hole in the pond side of the pipework just below that level. During normal operation the amount of water that is drawn through this hole rather than from the bottom drain will be negligible but, if the water level ever drops below the hole, it will suck air and kill the syphon.

You can refine the idea by fitting a self tapping air line nipple with a valve into the hole. That way you could close the valve if you did a large water change but still wanted to keep the equipment running. Of course, if you did this, you should do it in a way that didn't allow the fish to harm themselves on it, I leave the method of protection to you but one idea that springs to mind is that a short piece of garden hose might fit neatly over the valve and cover it. Also, it would be a good idea to check it occasionally to make sure it hasn't become blocked by algae growing inside it.

If that idea doesn't suit, you could use a float switch connected to an audible alarm, such as a door bell and transformer, that would attract attention more reliably than remembering to look out of the window. This would attract attention even during the night but bear in mind the neighbours so you might consider running the alarm into the house. By using a low voltage transformer it would be safe and easy to clip the wire along the fence.

[maxinegrundy]

Hiya
Its hard of you go away so much to keep a more personal check on them ..
CCTV is a godsend for me ..it has smartphone app so i can have a look at what they are up to while i am at work.
When it gets round to this time of year when the covers go on .. i move the cameras so i can see inside the covers.
If i see anything not quite right i can call my neighbours and they will go check for me ..
But one of my first jobs of the day is to go round and check that everything is running and then again when i get home
...only on the odd occasion i have found something wrong.
paranoid .. maybe well yes i admit it .. i couldnt go a week without checking them LOL
Maybe you could con the kids into a bit extra spending money if they do the pond check every day ..
and so you know they have done it get them to record the pond water tempreture
plus that will hopefully create a further interest for them other than just feeding
Max