Direct sunlight

[juniors04]

Is this bad for fish?

 

[shrimpy brains]

I don't think so. It can however give you major algae problems.

 

[aquaknight]

Seeing how probably 90% of fish we kept, esp. larger fish, arrive in your tank from the wild, no, direct sunlight is fine for them.
But as Shrimpy mentioned, any tank I've had setup that was exposed to direct sunlight, seemed to have some algae problems, or at least I had to scrape the glass more then I cared for.
And I don't mean this to be insulting in anyway, I'm just curious as to how you figured it could be potentially harmful?

 

[fishtaco]

Not the original poster, but maybe the sun going through two layers of glass could have a magnifying effect. Just a corner of one of my tanks gets direct sunlight during parts of the year and it seems very bright.
Fishtaco

 

[aquaknight]

Nah, the glass on either the tank or window would have to have some type of convex lens shape, like "()," that would aim the light beams together to up the intensity. Every tank and window that I'm aware of, including circular goldfish bowls and bowfront are still 'flat' glass, that does not re-direct light.
In actuality, the glass would lower the intensity of the sun, a touch or two.

 

[jetskiking]

Only tanks I have seen successful in direct sunlight were fed from the ocean and basically undergoing a continuous waterchange. There is an outside tank at the aquarium in hawaii that has tons of SPS. But anyway to answer the question it won't hurt the fish

 

[nuro]

it wont hurt the fish with the lightm but watch your temps. direct sunlight can blow up the temp pretty quick.