Algae outbreaks

[lisa73]

Hi, I recently brought a new aquarium for my plague catfish and guppies as the previous aquarium was leaking, I transferred all the equipment to the new tank and filled it with most of the water from the previous tank, I waited a few days before introducing the fish into the new aquarium, all was fine for a few weeks now, but in the last week the water has become very green and I’m struggling to get it clear again, I turned the light down, but should I turn the light off completely? Or is there something else I can try. I have attached a picture. Any help would be appreciated.

 

[Andy Sager]

Algae requires 2 things, light and food. If it doesn't have both, it doesn't grow so you have to address both issues. Yes, if you do not have live plants, just keep the light on during the hours you are mostly likely going to be viewing the aquarium and avoid natural sunlight hitting the tank. Test the water for Nitrates and/or phosphates as they are the food source for most plants. Since you have a lot of algae growing in the water, I suggest you use either a coffee filter or some filter floss to run the water through before testing it. This way there will be no issues with color results.

 

[Aiken Drum]

Is your new aquarium in the same location as the old one?

Algae is caused by an inbalance of nutrients and light.

I can see a window in the reflection so we have a very bright light source. Do you know what your water parameters are? Did you manage to retain your cycle when you moved the equipment to the new aquarium.

3 options really.

• Lower the lights, close the curtains or blinds, up the water changes, and over a period your green water should slowly clear up.
• Completely black out the tank. Only feed in the dark, after a couple of weeks your water should clear, your cycle should establish, and when you return light to your aquarium make sure its more under control.
• If all else fails, get a UV steriliser.

 

[lisa73]

Yes it’s in the same place as the old aquarium but this one is on a taller stand so I think you guys are right with the light from the window. I’m south facing and in a high rise block of flats so it’s very bright in the afternoon, I’ll close the blinds. I’ve left the tank in the dark today. So I can feed the fish in the dark ?

 

[lisa73]

Algae requires 2 things, light and food. If it doesn't have both, it doesn't grow so you have to address both issues. Yes, if you do not have live plants, just keep the light on during the hours you are mostly likely going to be viewing the aquarium and avoid natural sunlight hitting the tank. Test the water for Nitrates and/or phosphates as they are the food source for most plants. Since you have a lot of algae growing in the water, I suggest you use either a coffee filter or some filter floss to run the water through before testing it. This way there will be no issues with color results.

thank you for the advice that helps a lot

 

[lisa73]

Is your new aquarium in the same location as the old one?

Algae is caused by an inbalance of nutrients and light.

I can see a window in the reflection so we have a very bright light source. Do you know what your water parameters are? Did you manage to retain your cycle when you moved the equipment to the new aquarium.

3 options really.

• Lower the lights, close the curtains or blinds, up the water changes, and over a period your green water should slowly clear up.
• Completely black out the tank. Only feed in the dark, after a couple of weeks your water should clear, your cycle should establish, and when you return light to your aquarium make sure its more under control.
• If all else fails, get a UV steriliser.

Yes I retained most of the cycle, the filter gravel and plants are all the same ones, I didn’t clean the gravel or plants and I left the filter in the old tank water

 

[Aiken Drum]

What are your water parameters?

 

[Andy Sager]

Yes it’s in the same place as the old aquarium but this one is on a taller stand so I think you guys are right with the light from the window. I’m south facing and in a high rise block of flats so it’s very bright in the afternoon, I’ll close the blinds. I’ve left the tank in the dark today. So I can feed the fish in the dark ?

Feeding in the dark will depend on whether the fish are awake and active or are sleeping because it is dark. Aiken and I have differing opinions on treating the algae with total darkness and the fish are going to act differently in them. This means you are going to have to judge for yourself how the fish are acting whether to feed them or not. A healthy fish can go many days without food so they won't starve if they are sleeping during the blackout. If you feed and the fish are sleeping, all you will be doing is polluting the water which btw, feeds the algae.

 

[lisa73]

I’ll hold off feeding them in the dark. I fed them this morning with the light off, just normal day light, the rest of the day I closed the blind and left their light off.

The nitrate level is a little high at 60 ! What is the ideal level ?
Ammonia levels are ok
Oxygen is ok I think the fish are swimming round not gasping at the top at all.

 

[Andy Sager]

I’ll hold off feeding them in the dark. I fed them this morning with the light off, just normal day light, the rest of the day I closed the blind and left their light off.

The nitrate level is a little high at 60 ! What is the ideal level ?
Ammonia levels are ok
Oxygen is ok I think the fish are swimming round not gasping at the top at all.

Nitrate should be closer to 0 if there are no live plants. 40 PPM is usually the top limit so the 60 ppm is a good reason why you have algae. That's its food. I'd start with three 30% water changes spread out over the course of 7-10 days to get the nitrates down low without shocking the fish. The low nitrates and lack of light hours will help kill off the algae.

 

[lisa73]

Ok I’ll do that and see how it goes
Thank you