Algae from direct sunlight

abcdefghi

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Jun 6, 2007
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I think I am getting some brown algae in my tank from direct sunlight hitting the tank at certain times of the day. I am not sure of the type of algae, but its dark brown and appearing on the gravel. Short of moving the tank what options do I have?

It's not a whole lot of sunlight, I have decorative glass on the door so its literally a thin line that comes through where the glass is clear, but it looks like enough to create algae.

The tank is planted, and the lights are on for about 9 hours a day.

Thanks.
 
Is it coming in the back or side of the tank? Or the front?

If it's the back or side, I would suggest taping up one of those black backgrounds to the tank to block it out.

It's coming in from the side and the front, it's during the evening when the sun is low enough it comes through and gets some of the front and one side.
 
If its a relatively new tank, less than 6 month, it could be brown diatom algae which should go away on its own - just a sign that the tank is maturing. Look up brown diatom algae for pics and see if this is what you have.
 
it's not so much the sunlight as the total tank light that can help diatoms grow. You can try reducing the photoperiod. lower nitrates will help fight the growth. This means either less feeding, or more frequent/larger water changes, or both. More plants can also help with this. Also, diatom growth is very common in new tanks, and will often resolve on it's own. How old is the tank? Oto's love diatoms, and I see that you have some, I'm guessing this is a different tank....
 
Correct me if im wrong anyone...ive been tainted by years of marine tank use.

Brown algae I can only think of 2 types that are called brown..Diatoms (feed on silicate) and Dinoflagellets (spelling way off im sure)...

The diatom is something that will pass in time just holding firm on maintenance. The Flagellets oh my i dont know if you fresh users get it...but if you do..that stuff is toxic.

Pics would be good to help ID....

I dont know if this would help but visit Chuck's Addiction

Go to hitchhikers on left column...then to algae ... take a look at some of those pics. It is marine based site..but...we share your problems in the fish tank world.

BGA is redslime for us... both cyano for instance...(bga blue green algae).

The thing is for fresh you all don't worry so much about phosphate as marine do....and use of tap water does introduce it. That is miracle grow for plants and algae... you also dont use intense lighting..so you dont experience as many headaches with pain in the butt algae.

IF you cant relocate the tank, you need to find a way to control your phosphate levels ...you may have too much... too little will screw the good plants up... this is an area I am not good with.. Planted tanks..

I believe you should check the planted section in fresh for those users advice ....
 
it's not so much the sunlight as the total tank light that can help diatoms grow. You can try reducing the photoperiod. lower nitrates will help fight the growth. This means either less feeding, or more frequent/larger water changes, or both. More plants can also help with this. Also, diatom growth is very common in new tanks, and will often resolve on it's own. How old is the tank? Oto's love diatoms, and I see that you have some, I'm guessing this is a different tank....

The tank has been set up for about 13 months now, so I would think that the diatoms from the tank being new would have worn off by now. However the tank has been moved, so not sure if that would have an effect.

Nitrates are already only around 5-10ppm, so not sure how much lower I could get them that they already are. The Oto's do a great job of keeping the plants clean, but they do not appear to be on the gravel that much. Maybe I need more? the 4 I have are fat, but I think I would be likely overstocked if I added anything more.

It looks like the only real options I have are less light and more plants. I will try to get a picture of the algae, but its the same as the kind that is usually seen growing on gravel.
 
If all else fails, keep in mind that the algae/diatomes are helping to maintain chemistry, and make happier fish. We just don't like to look at them.
 
I'd say reduce feedings, buy some shades for the window, and up the gravel vacuuming.

They only get fed once a day, and a fast day during the week, shades for the window would not work (its the front door) and they already get a good 40% water change/gravel vac weekly.

:)
 
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