Brown Algae?

[Dano]

My 29 gallon tank has been set up for around 6 months now but for the last week it's been starting to grow alot of brown algae in it. When I first started my tank I had 2 fantails but gave them away a little over a month ago and did a 50% water change after I gave them up. I now have 6 zebra danios & 6 black skirt tetras & it didn't start growing until I got them. I do my weekly 15-20% water changes & haven't missed one. I also have a 10 gal tank with 2 fathead minnows that has been set up for a year and it doesn't have any algae. Is it common for brown algae to grow in tropical tanks?


my Tank Stats....

60 Gallon whisper filter
2 air pumps at each end of the tank with small air stones
Temperature In tank is at 76-78 degrees

my test results are staying the same...

Ph: 7.6
Ammonia: 0 ppm
Nitrite: 0 ppm
Nitrate 10 ppm

I can't get the nitrate down lower because it's they same as what comes out of the tap.

[AquaBANG]

what about the lighting?

[Dano]

what about the lighting?

Opps forgot about that. I leave the light on for 6-8 hours a day.

[karbomb]

could be due to overfeeding, but your tank parameters look good. algae is a naturally occurring thing. does your tank receive any sort of natural light?

[Dave66]

My 29 gallon tank has been set up for around 6 months now but for the last week it's been starting to grow alot of brown algae in it. When I first started my tank I had 2 fantails but gave them away a little over a month ago and did a 50% water change after I gave them up. I now have 6 zebra danios & 6 black skirt tetras & it didn't start growing until I got them. I do my weekly 15-20% water changes & haven't missed one. I also have a 10 gal tank with 2 fathead minnows that has been set up for a year and it doesn't have any algae. Is it common for brown algae to grow in tropical tanks?


my Tank Stats....

60 Gallon whisper filter
2 air pumps at each end of the tank with small air stones
Temperature In tank is at 76-78 degrees

my test results are staying the same...

Ph: 7.6
Ammonia: 0 ppm
Nitrite: 0 ppm
Nitrate 10 ppm

I can't get the nitrate down lower because it's they same as what comes out of the tap.

Brown algae is simply diatoms. They proliferate when there are sufficient silicates and nutrients in the tank. They nearly always show up in newer tanks, like yours is since you changed it to tropical. Over time as the tank matures they'll go away. You can scrape the glass if they bother you, but they are harmless, if unsightly.
If you've a canister filter on the tank, you could accelerate the diatoms' demise by placing one of the phosphate/silicate removal substances in one of the filter baskets. You can also lengthen the photo period, as diatoms don't like bright lights.

Dave

[plow]

So Dave, If I wanted to grow brown algae could I shorten the photo period?

My tank had loads of brown algae so I intorduced 3 oto cats and they cleaned it out in 3 days..

now I am concerned they are not getting enough to eat, so i'd like to get some algae back.

[Dave66]

So Dave, If I wanted to grow brown algae could I shorten the photo period?

My tank had loads of brown algae so I intorduced 3 oto cats and they cleaned it out in 3 days..

now I am concerned they are not getting enough to eat, so i'd like to get some algae back.

Plow,
You'd need to add silicates to the water to get the diatoms going, but there's no reason you couldn't just feed the Otocinclus vegetables. I've written several posts about feeding Otocinclus.
Or, you could put the tank near a window so it'll get about four hours of sunlight a day and overfeed the fish a bit. Then you'll have enough green algae for your Otocinclus, which is their natural food anyway, but you should still give them veggies every day. Takes a lot to keep those little herbivores going.

Dave

[Dano]

I got rid of all of it and also got me a rubber lip pleco. Thanks everyone for the help.