Algae Control - UV? 

Consumer Question:

"I had an 11 x 16 foot Aquascapes Design pond put in last September (2003) and despite all of my efforts and direction following from the Aquascapes site, SAB, Aquaclearer liquid supercharger, I still end up with a dark green pond. Fish and plants are all healthy, but pond is very dark green. Aquascapes doesn't believe you need a UV Sterilizer on the pond...wait 6-8 weeks they say it will clean up. By then our pond season here in NJ will be over. Should I put in the UV Sterilizer or not? It is not a question of money. What type would you recommend if so? "

Thank you, Heidi

Doc Responds:

UV works well on Aquascape installs. It can be plumbed inline between the pump/skimmer and the falls. You might have to do a major water change before the UV can get a grip on the condition - this is because dark green water won't allow the light to penetrate the water, so it will fail. If you do a major water change, making the water transluscent, the UV light will be able to "dig in" and kill off a lot of algae, clearing the pond in a couple days.

Dead algae can consume oxygen, and the decay of trillions of algae organisms will tax your filtration for a time. Another water change is conceivable.

The UV should have sufficient size for the FLOW RATES - and for the size of the pond. Don't invest in a UV with smaller than 2 inch porting.

So, you're at the mercy of the installer or the salespeople to advise you correctly.

I am particulary fond of the Emperor UV for small to mid size ponds, and the Zapp Pure for the bigger ponds. You should do a keyword search for these, I won't direct you to a retail site right now.

BEWARE of retail sites that sell "everything" including six or seven ultraviolet sterilizers. For example, to be complete, companies like Fosters and Smith sell "everything" which necessarily includes a lot of stuff that doesn't work, AT ALL.

Find a company that tests what they sell. It will reduce the selection, but it will reduce the chances of you buying something 'on price' that in fact does not even function as it should.

So, yes, a UV would help you.

Normally, (as in my Aquascape pond) the plant growth is high and the fish load is light and feeding rates are reduced [necessarily]. Then, the green water issue DOES resolve itself without the UV deployment.

Erik