Green koi pond water

[Jacychan1]

Hi i was wondering if anyone can help, i have a 2500ltr pond with 6 goldfish 2 carp and a white koi in, i purchased a pump and filter set that should pump 2500ltrs an hr but my pond is still water is still green even after 3 months of running and 4 cleans, i was wondering if i bought the wrong filter system? If i could get a steer on the right one to buy that would be a missive help, thankyou.

 

[Mmathis]

Hello and welcome! Green water is common after a new startup.

When you say “4 cleans,” what do you mean? What are you cleaning? And if it’s the filter media, how are you cleaning it? Don’t want to overwhelm you with information, so will wait to see your answers.

You will find that we like natural filtration — using plants to filter the water. We recommend bogs!

 

[JRS]

Welcome! Your average filter system, unless it has a Ultra Violet sterilizer is not going to help with the green water which is growing on the nutrients in water that are not filtered out.

 

[GBBUDD]

IT'S ODD THIS IS A GARDEN POND/ BOG site by a Brit yet i can't think OF ONE BOGGER in Britan that comes here

 

[j.w]

@Jacychan1

 

[Jacychan1]

Hello and welcome! Green water is common after a new startup.

When you say “4 cleans,” what do you mean? What are you cleaning? And if it’s the filter media, how are you cleaning it? Don’t want to overwhelm you with information, so will wait to see your answers.

You will find that we like natural filtration — using plants to filter the water. We recommend bogs!

Hi its a well established pond, i replaced my pond pump with a pump and uv filter, on paper it said it could handle my pond size but even after a few months the water is still green, ref cleaning i opened up the filter system and cleaned the sponges, im unsure weather to buy a even bigger filter system or just add another pump and filter, ive also tried an algae treatment which works for a week but then the water starts going green again, im pretty new to this pond stuff so apologies for any stupid questions.

 

[Jhn]

If your pond is well established/mature, the issue is your filter can’t keep up with your fish load. Your pond isn’t that large, to keep it balanced I would get rid of the carp and koi, just sticking with goldfish. Adding lots of plants to the pond will help outcompete the algae for nutrients starving it out.

Regular off the shelf filters while not bad aren’t that great at eliminating nutrients from the water. The algae your experiencing feeds off nitrates/phosphates, which your filter does nothing to eliminate, even the UV light is a bandaid. It will kill the free floating algae, but unless you have someway to remove it from the system, the dead algae will fuel another algae bloom and the cycle continues. Also, don’t add chemicals to kill algae, these treatments at best again are bandaids and at worst can lead to fish kills in a pond.

Regularly clean your filters, add plants, reduce fish load, increase circulation, add a bog filter if possible, the cause of your green water is excess nutrients in your pond. The above mentioned solutions will target that.

 

[Lisak1]

Good advice from @Jhn

Welcome to the GPF!

 

[addy1]

Welcome to the forum!

 

[poconojoe]

First of all, your pond is too small for koi and carp. You probably don't want to hear that, but that's the root of the problem. Too much fish waste which feeds the algae.

Add LOTS of plants to compete with the algae.

@Jhn Is spot on. Great advice.