Need help with algae problem

[DiVerz]

Hi all

I have approx 20 goldfish, not sure what breed, that have lived happily in a pond for many years.

I have recently had to destroy the pond due to renovations and have moved the fish into a tank.

While in the pond the fish lived solely on the algea and veg matter that grew in the pond. I regularly topped up the pond with plain tap water and it had no ill effect on the fish.

Since moving the fish to a tank I want to keep the water clear but no matter what I try the water becomes green with algae within hours of cleaning the tank.

We can use pure tap water with chlorine etc in a clean tank without any ill effect on the fish but just can't keep the algea from growing back.

I have also used an anti algea chemical in increasing doses and constant running of a filter again without any noticable effect on the fish but it makes no difference to the level of algae.

The fish seem happy as long as they are in water and have food.

I will be happy if we can see them in the tank rather than quick flashes in the green murk.

If anyone can provide some advice it would be greatly appreciated.

Thanks in advance.

D

[fishbites]

Welcome Diverz!

Lots of algae = lots of light + lots of nutrients in the water

Reduce both and the algae won't grow.

(remember with goldfish they can make a mess if fed too well in a tank - what goes in one end comes out the other!)

Hopefully after your renovations you can put another pond in for the fish.

How big are the 20 goldfish and how big is your tank? What type/size filter are you running? If the 20 goldfish are the size of those in my pond you would need a pretty large tank (at least 6ft) to house them comfortably.

Is your tank artificially lit? If so reduce the number of hours the light is on and reduce the amount of food.

If it's in direct sun there's not much you can do apart from shielding the tank a bit more from the light and see how that goes....

[Chuckie]

Ironically, adding un-dechlorinated tap water to your tank (which only has no visible ill-effects on the fish, FWIW - it still strips off their protective slime layer and irritates their gills) is killing the beneficial bacteria in your tank that might help keep the algae under control. As well as maybe covering the tank with a towel or something when you don't need to be looking at it (to reduce the light that the algae uses to reproduce and grow - we call this a black out), also use a good water treatment like Prime and let your beneficial bacteria get a foot hold.

[Terribletegs]

My mother had a similar problem recently in one of her tanks. She took down the tank with all equipment and washed everything in super hot water. She then set the tank up again and the algae didn't come back.

[zhong89]

I had the same problem back when i first started to keep goldfish. I just can't seem to get the algae to go away, I didn't like the idea of putting extra chemicals in there to kill it since I don't know how it will affect my fishes. Since algae = too much nutrients, I solved the problem by add a plant to the tank. The plant I added to my goldfish tank is a banana lily, they're cheap and hardy and loves the light you turn on to make your tank look nice and pretty at night. The plant used some of the excess nutrients in the water making it hard for the algae to grow.

I hope this helps