ok bottom drain is central length wise in pond but close to one edge not aerated.
Filter is fluidised k1 on separate air pump
Is it best to put numerous 2" air stones round the pond edge OR the 6" ceramic somewhere in the pond? If so where?
The ceramic really boils the water
I tried one of those round ones over the drain but they are rubbish as they use smaller air line and seem to need a lot of pressure so other airstones have easier flow off the manifold then the air goes to them... If you know what I mean....
Andy,
The reason that you see so many people recommending the use of airated bottom drains is due to the tremendous difference that they make in keeping the bottom of the pond clean.
If you picture all the air rising from the airated drain, when it reaches the surface it pushes the water out towards the edges of the pond. The water then sinks against the walls, and is then drawn back to the bottom drain, completing the circle, sweeping the floor and taking any debris with it.
Bearing this in mind, I would suggest that you put your ceramic air disk on top of the bottom drain, and forget about using lots of small air stones spread out round your pond. At least it will give you similar circulation to an airated drain.
i'd have to agree, stick the ceramic disc on top of the bottom drain cover. and all the other air in some uplift tubes (big ones) running the filter or just hung over the pond side ( remember no air stones needed) ` it'll move more water than any airstone..
this'll give you hours of fun playing with different diameters, lengths and sizes of air-pipe....
Andy,
It is the fact that bottom drains HAVE covers that make them so effective at keeping the bottom of our ponds clean.
Basically, its like blocking off 90% of your vacuum cleaner hose, and then feeling the increased suction that it gives you. With a bottom drain cover set to about half an inch from the pond floor, it is amazing the pulling power that results, which of course keeps the floor `swept` of all the fish mess.
Without a drain cover at all, you are relying on any muck in the water to `happen` to be floating by and to be lucky enough to fall in just the right place to make it into the drain. If it misses and lands on the floor, there it`ll stay till the fish or water currents move it.
OK so I reckon the 20yr old drain is probaby 8" dia so I may be able to put the ceramic on top and leave room for water pull through.
Unfortunately the only way to see if this is possible would be drain the pond or get the scuba gear out.
I may do this at some point, although it would not make the fish happy with me in there.
Not gonna be easy trying to wiggle cable tie in and out of grid though.
Apart from a re-build my only sensible option is refit a new liner next year so poss fit new drain then?????!!!
I get the bit about restricting the hoover
Do these drains throw up air from just above a dome covering the drain??? I reckon If I covered most of the drain with a ceramic then if i still had
ONE section(the outer diameter) exposed then it would work.
How about using an upside down plant-pot saucer as a drain cover? Better still, get a ceramic one as used for the `classy` tubs.
Stick some sort of spacers on that are about half-three quarters of an inch high (below the rim), maybe pill bottle tops or similar, and stand it over your drain. Put your air disc on the top and away you go!!
Chris (another one)
edit, forgot to answer your question, but yes, the air diffuser covers the top of the drain cover. In the early days they WERE domed, but nowadays they are flat.
it'll move more water than any airstone..