7 July 2015

A Wet Weekend

The theme of this year's summer seems to be 'Water'.

For some reason unbeknown to my Reason I've chosen to respond to this theme by getting even more involved with water by fussing over one of the ponds in Garden65.

Whereas the bigger pond had an algae problem (solved by our ramshorn snail friends), the little pond is suffering from a degree of dullness. It is doing fine, ticking along without any major problems, but in the past the water was clearer and sparklier. A predicament I can empathize with. 

The first step to clearing it up is to hoik out the bottom mud.  Now, I have some toleration for the grubbier elements of the garden: hoverflies, snails, even at a push, slugs, but I really don't like the nasty things at the bottom of a pond. I can take a spider - they may be scary, but are quite sexy really, like wolves, but those jelly-fied things that live in the muck in a pond just give me the willies. So this phase of the operation was necessarily short.

The next stage, filtering the water, is much more engaging.

The proper filters that the big boys of the pond world have are too expensive and serious for me, so I'm trying to rig up a homemade filter system.

Attempt 1

Laundry bag stuffed with cut up bits of cheap sponge tied to underwater inlet of waterfall pump.

Problem - bag floats

Attempt 2

Laundry bag and its sponges at other end of pipe in the waterfall itself, weighted down with large stone from a Danish beach.

Problem - still floating, and sponges not that efficient

Attempt 3

Applying greater complexity: old seed tray with holes in the bottom, lined with cotton quilt batting, topped with the increasingly unpopular sponges.

Success - mud now being filtered out of water - hurrah!

Problem - sponges losing all credibility as dirt filters. Flow of water from pipe is delivering more water than the seed tray can hold, resulting in overflowing muddy water getting back to pond.

* Note: at this point a drop of pond water shot directly up my left nostril. If I don't post in the next few weeks assume I'm ill with some nasty water-borne disease.

Attempt 4

Deeper container - the top bit of small barbeque. This time lined not only with batting, but also pads of wool from an Abel & Cole box.
Sponges given last chance to redeem themselves by catching any overspill.
Success - rate of inflow and outflow nearly equal. Mud being filtered.
Problem - not quick enough for my liking. Where's the crystal clear water?
To be fair the cobbled together filter is doing its job. The water is better:
Water flowing out of  'filter' on left.   Water flowing in on right.


The conclusion from all this Heath Robinson experimentation is that synthetic sponges don't filter water, but wool does. Perhaps it is something about surface area, or maybe electrons attaching to molecules ... I don't know.

The next step, if I'm not in an isolation ward, is to redeploy more Abel & Cole wool, and be more patient.