Re: Cloudy brown water - Three fish dead - HELP!
#9
Have you walked the pond to see if there is anything dead in there, eg fox, dog or cat etc?
Have you had a large scale plant die off recently, that would give rise to a lot of rotting plant matter?
Rotting anything may remove oxygen from the water and add noxious gases to the water.
Honest suggestion, go to the likes of B&Q and get one of the 10ft dia 2ft or bigger deep paddling pools, the ones with the floatation collar like top, £60ish, and set that up in the shade as a temporary pond. Fill it with either pond water or tap water treated with dechlor, I'd be inclined towards the latter, and move your remaining fish and lilies etc.
Set up a descent sized pump, say 3000lph, and rig up a 'falling water' return to oxygenate the water, ie have the return from the pump drop say 1ft into the centre of the paddling pool. A net to keep the heron off may also be wise.
Then investigate the pond. If you find something dead in there I'd dump all the pond water and start afresh
If there is a thick layer of sediment on the bottom remove all but say 1/4". I too would add more plants, say hornwort, rooted oxygenators take longer to establish unless you buy in large quantities. Azolla might be useful but harvest that, COMPOST the surplus DO NOT dump it in a waterway and COMPOST all of it when it turns red.
I think you should also look at setting up a pump etc in the pond with a bigger flow rate than that spitter and probably a external filter too, I hate over the side plumbing or wiring and would think about running plumbing and conduit if needs be through the liner towards those bushes on the right. I use plumbing solvent weld "overflow" pipe as conduit and make any 90deg bends required via 2, spaced out, 45deg bends, that way you stand a fair chance of being able to push feed a cable around a bend. Or, if that pier is suitable put a filter etc inside there under the flagstone. If your flagstones are 2" thick they should span a 2ft wide filter chamber. If you have a weak or dodgy back that you may need to think up some other form of cover, a 2" thick flagstone is an appreciable lift. I know, my pump chamber has 2 slightly cut down 3ft x 2ft x2" flags over it.
Re adding tap water straight to the pond, turn the spray gun the other way up so that the spray travels up into the air before entering the pond.