Surface Algea

[mrpizz]

Hi all, I have a 260l planted tank which has been running for around 4 months. all fine and fish doing well until earlier this week when i noticed a little green algea floating on the surface. This has now increased to the point where it has completly covered the surface. The rest of the tank seems ok, with just a little algea on the rocks which i clean off each week when changing the water.
The tank stats are

Amm 0

Nri 0

Nra 5

Ph 7

Fish are 4 black ruby barbs, 7 cardinal tetras, 4 mountain minnows

Thanks

 

[lilfishie]

is the tank in direct sunlight? how long do you leave the tank light on for?

 

[mrpizz]

Tank not in direct sunlight. Lights on for 10 hours per day

 

[lilfishie]

how often and how much approx do you feed?


the main causes of algae is extra nutrients, which can be caused by too much light or excess/uneaten food, try cutting down your feeding and the amount of time the light is on

 

[mrpizz]

feeding once a day, approx 15 flakes

 

[loadsa]

Never seen a floating algae you sure it is not duckweed

 

[mrpizz]

No definetly not duck weed, its a very fine green film on the surface of the water, it has developed over the last few days. I have just noticed a small amount of algea on the mopani in the tank, I am going to reduce the time the lights are on and reduce the feed slighty to see if that makes a difference. Am thinking of adding a couple of Otto's to.

 

[loadsa]

Have you tried breaking the surface with a spray bar or even a powerhead

 

[mrpizz]

Sorry about the delay in replying, my filter breaks the surface, i have now reduced the lighting to 8 1/2 hrs per day, reduced the amount fed slightly and added 3 ottos, i have also bought a test kit for phosphate which is at 0.25
I have been carrying out 2 25% water changes a week which reduces the "green film" but within 2 days it is back again.
Can anyone suggest what my next move should be before i go mad!!

Thanks

 

[Matty P]

If the surface agitation doesn't remove it, investing in a UV sterilizer would be a wise idea. It is very efficient at removing free swimming algae form your water.

Matt