Am confused, when should I switch my UV filter on?

[CeeJayH]

I've just finished a new pond, 4,000 litres and it's had water in it for a couple of weeks. I have a biological filter with an inbuilt UV chamber attached to a pump rated at 3,500 lph, so it's pumping the pond volume through in just over the hour. I have planted it up with three lillies, and a number of other plants. I haven't introduced any fish yet.

A few days ago, the water went pea soup green, which (based on what I've read in numerous threads) I was expecting. I expect it to clear as it cycles and the bacterial colony in the filter gets established. The one point I'm not sure about is whether to run the UV filter yet, and when to start it?

I'm sure a resident expert will set me straight.
Chris
PS I've created a showcase on the pond if you want to see what it looks like.

 

[dieselplower]

Whenever you want. Some say turning on a UV may cause the pond to take longer to cycle but the extra length would be negligible IMO.

 

[CeeJayH]

Thanks for the prompt reply. I hope with the number of plants in the pond, it won't take too long to settle down.

 

[waynefrcan]

I think you should wait until the pond cycles. I read somewhere, when the pond is first starting the bacteria are water born and will be killed, taking much longer to a pond balance.

 

[fishin4cars]

Normally I would say turn on the UV as soon as you start seeing green water. But since this is a new pond I would also agree on waiting for the pond to cycle before trying to clear it up. green water isn't going to hurt anything at this point in the project and the algae may use up most of the excess nutrients in the water before the cycle is even complete if your not adding more nutrients such as fish food, fish waste, etc. However, there is still a need for something for the bacteria to feed on to start the cycle.

 

[dieselplower]

Normally I would say turn on the UV as soon as you start seeing green water. But since this is a new pond I would also agree on waiting for the pond to cycle before trying to clear it up. green water isn't going to hurt anything at this point in the project and the algae may use up most of the excess nutrients in the water before the cycle is even complete if your not adding more nutrients such as fish food, fish waste, etc. However, there is still a need for something for the bacteria to feed on to start the cycle.

But if you leave the algae, it will consume the ammonia the bacteria need.... It's really a toss up.

 

[waynefrcan]

I packed my UV away for years when I was told that it killed good bactaria as well as bad and the ugly pathogens. I would plug it in with convincing proof it kills very little good compared to the rest.

 

[fishin4cars]

I was under the impression that plants didn't use ammonia, I also thought that plant life used nitrogen and phosphates which is also what algae fed off of. That's why I have always left the green algae in place until the cycle was complete before trying to combat it.

 

[dieselplower]

I was under the impression that plants didn't use ammonia, I also thought that plant life used nitrogen and phosphates which is also what algae fed off of. That's why I have always left the green algae in place until the cycle was complete before trying to combat it.

http://www.koiphen.com/forums/showthread.php?29859-Does-Algae-Absorb-ammonia-nitrite-and-nitrates

http://www.ysi.com/media/pdfs/A585-Understanding-Ammonia-in-Aquaculture-Ponds.pdf