As predicted our koi pond is "somewhat" green despite having (supposedly) oversized bio filters with UV and several m² of water hyacinth growing like crazy in separate filter beds.

Our chooks like to eat water hyacinth so we have an endless free supply of chook food

I don't feel like trekking round JJ in the heat so does anyone know of a decent online shop for koi water treatments etc.

Not looking for crystal water, just to have a chance of seeing the fish

If your Pond water is not clear,the first thing to look at is your U.V. Lamp,

what wattage is it, when was the bulb last changed or even cleaned,and

what is the water flow going through it.

Also a cause of green water is over feeding,I buy a Kg of frozen corn from

Makro,it's a nice change for them,over feeding the pellets can pollute the

water.I don't know any online store in Thailand,there is quite a few decent

stores up here in Chiang Mai,anything I need ,if it's not too heavy,i get my

daughter to post from UK,she also brings things I need when she comes

to visit.

Regards Worgeordie, P.S. if you plan to use an algaecide,could damage your plant filters.

I have exactly the same problem and googling around ( I would be prepared to travel to Bangkok if necessary) hasn't been of any use. I agree about overfeeding though, my wife seems to think that the more the better. Emptying the pool again today, which the fish don't like

Yeah, one of the reasons I want a decent store to look at is that I strongly suspect the UV at 2 x 10W is well undersize for the pond which is about 20,000L and has little (ok, no) shade.

I'm looking at the 75W Evolution Aqua evoUV, here http://www.ebay.co.uk/itm/331645935374?_trksid=p2060353.m1438.l2649&var=540934481805&ssPageName=STRK%3AMEBIDX%3AIT which is one of the reasons I'm interested in the discussions about Ebay's Global Shipping Program (and how useless it is).

The UV units I see in the big box places are cheap Chinese plastic and have minuscule maximum flow-rates (cheapo 36W @ 700 L/hr, compare with the evoUV 30W @ 15,000 L/hr [yes, that is the right number of zeros]), I'm looking for decent quality which stands a chance of lasting for a while, I don't mind paying for it.

I can put the UV on a timer once the green has diminished to extend the tube life (and reduce the power bill).

The water isn't cloudy so my particulate filters (one foam and one Zeolite) seem to be catching the bigger stuff, just the tiny green chaps whizz straight through.

I ended up getting two of these from the UK :-

They are not cheap at 140 Quid a pop, but nicely made (in the UK) and with a decent spec.

All in, including shipping, VAT and duty cost was 368 Quid, her ruddy fish are costing me the earth, but they look nice.