Some pond questions ..

[T i m]

Hi All,

I popped in on some friends today and when I got there they were 'de weeding' their posd.

It's about 5m x 3m and made of that black flexible sheet that you lay into a hole, fill with water and trim round the edge.

1) They said there are a couple of leaks (one was made by them by cutting in the wrong place and the cause of the other is unknown) and both are near the top edge. They have tried what sounds like double sided tarmac (supposed to cut a patch from some spare material, warm it up peel the backing paper off and stick it to the patch then peel off the other side and slap it on the dry pond surface etc) but they said it didn't last long?

So, do you need to know what type of material it is to suggest a suitable repair or is there something 'miracle' out there? (Or maybe they just didn't do it properly)?

2) There are no fish in the pond (there were some, but one big one ate the little ones then a heron at that!) but apparently it builds up with algae / weed regularly. They were thinking of adding some sort of pump / waterfall in a hope that it might help to keep it clear? Would it?

They are hoping to just have it as a lilly type pond and maybe attract some ducks etc?

All the best ..

T i m

[geoff]

In message , T i m writes

There are two common types - pvc and butyl

Butyl is much more "plastic" than pvc

I have an ultraviolet filter which sort of works. Lillys are a good idea as they reduce the quantity of sunlight which actually gets into the water

[Michael McNeil]

Try here:

[T i m]

All the best ..

T i m

[Wanderer]

Good ones use a butyl rubber liner, cheap ones use a black plastic liner!

It'd be worth going to a garden pool specialist if they haven't already done so for a repair kit. Alternatively, try a swimming pool place. They sell repair kits for liner pools, but I guess it depends on whether it's rubber or plastic liner.

Nope. I have a biological filter, a u/v treatment lamp, and a water fall, and still the stuff forms. The waterfall clogs up in about three or four weeks at the height of summer. They might do better if they're not keeping any fish, as I think it's the waste products from the fish that enrich the water and promotes the growth of blanket weed. I use pond balance periodically to try and keep the weed in check.

[Lee]

I know someone with a Koi pond, all the usual filters, UV etc, but he's also gone for depth (4m) and has lots of planting in the bottom and around the edge in an attempt to soak up the excess nutrients.

What seems to help most though, is that he has a gazebo type affair over it to keep out direct sunlight. Although it doesn't stop the weed completely, it does appear to reduce it.

Lee

[Michael McNeil]

I just took a look at the ponds site and found this:

what is the lightest widish bridge design you can come up with? My suggestion is 3 or 4 short scaffold planks fitted with cleats to hold them in between the rungs of a pair of aluminium ladders. The idea being that you get a free ladder out of it with the removable base easily stored/stacked.

[T i m]

Thanks again to all those who have replied.

So, the consensus is that just moving the water alone won't inhibit the build up of algae and weed.

Restricting sunlight and minimising nutrients (or consuming elsewhere in plants etc will also help.

The owners of the pond said they had asses some chalk like material that kept the pond clear for a couple of years but can't remember what is was?

All the best and thanks again ..

T i m

[Lee]

Are you sure it wasn't lime or even normal chalk? Make the water alkaline enough and the weed won't grow... but then neither will anything else :) Or it may be a nitrate absorber, removing as much nitrate as possible would obviously help to keep the weed and algae down. Trouble is that it would also stop beneficial planting from growing, and you said they wanted lilies... :)

Lee

[Owain]

"Michael McNeil" wrote | I just took a look at the ponds site and found this: |

| So what is the lightest widish bridge design you can come up with?

a 60m Clear Span, GRP Composite Footbridge like one in Aberfeldy?

location Ordnance Survey Grid reference NN8649. A new footbridge joining two halves of a municipal golf course. Entirely built from composite materials. The main span of 64m consists of GRP deck with GRP towers. The stay cables consist of aramid fibre parallel-lay ropes.

Owain

[N. Thornton]

The lightest would have to be a rope bridge. The lightest sensible design would have to be 2 aluminium poles plus ribbed ali flooring, or in the real world 1/4" marine ply.

Regards, NT