Bettas, aquarium light (not for heat) and health

[TokyoBetta]

Hi all

I recently had a bit of an algae outbreak and it negatively affected my fish.
I'm sure it was giving him some kind of problem which resembled Velvet, (he was kinda dusty and lethargic). I gave him a nice water change with some aquarium mineral salts and boiled the heck out of all the stuff in the tank.

I also stopped using the light because it leads to algae.

He seems better now overall.

But now that I don't use the light, I find he's a little more lethargic and just floats around.
Sometimes I tap the glass and get no response, leading me to think he's sleeping.
He has no visible symptoms of anything listed in any Betta disease FAQ's.
I will be starting a natural garlic supplementary meal soon though just in case, for parasites.

And...I just turned on the light and he's swimming around now some more.
I don't want to leave it on too long though because I'm afraid it will bring back my algae problem.

***So here's my question(s):***

How much direct light do they need to thrive?
Do they become listless with a lack of light and a little perhaps dopey or constantly sleepy? Kind of like humans and seasonal mood disorder.
Humans need light for Vitamin D production - is light somehow necessary for body rhythms and whatnot with Bettas too?

They are afterall tropical fish.

Thanks

[1fish2fish]

They should get at least 4 hours of indirect light a day IMO. I have a fish who doesn't like tank lights but still gets light from the room daily. As for the algae.. it usually doesn't harm the fish.. if it starts to come back just start scrubbing it off daily (as well as doing a pwc) and eventually it should go away entirely.

[dr2b]

Bettas need a day and night cycle just like every other living thing. How long were you leaving the light on in the tank before? What size tank is it? And what kind of bulb do you have in the tank? Once these are answered, it opens up more options as to how to help you. :)

[TokyoBetta]

It's a flourescent light, 'white' and I had it on about 18hours a day sometimes.
My tank is just under 5gallons. Basically while I was awake it was on.
I put it there for the grass, but the grass died anyway because the roots didn't take.

I think you're right about algae, I did some more reading and it shouldn't really affect him.
The dustyness must have been the onset of something unrelated.

I'd still like to keep the algae away though, and also do what's best for Sam in terms of light exposure at the same time if at all possible.

[dr2b]

You had that light on way to much. That is why you were having such an algae problem. If you don't have live plants in there, I'd leave the light on for Sam 5 to 7 hours max. The algae really doesn't effect them, as 1fish2fish said, it's just a nuisance to you. :)

[ScuitoAmi150]

My bettas don't really care about having a light. They get whatever light comes into my room in a day, and then the light from when I have my light on. The 6 bettas on my dresser get more real light than Ami who is across the room, but she is one of my most active fish.
As long as Axel has his plants he is happy. Scuito might like a little more light, he sleeps a lot, but he is also older (I've had him for 1 1/2 years, & he was full grown when I got him). When I first got Dragner, the only time he would ever swim around was when it was dim in my room. Weird, I know. Now that he has a heater, he swims around a lot more, with the light one. The three girls always swim around.

[1fish2fish]

I leave my lights on anywhere from 5-10 hours a day. Usually its a mix of light from the window and room and actual aquarium lights. The aquarium lights are usually only on from about 6-10pm.