Lighting Change = Behavior Change?

So, for a while my fish have taken to chilling towards to top of the tank acting like they're ready to be fed, more or less negating all the aquascaping I've done for them. Out of curiosity, I folded up a few pieces of paper and blocked out probably 3/4 of the light leaving a couple slits towards either side. Within 15 minutes all the fish gravitated towards the bottom and began acting more naturally. Obviously paper can't sit that close to an aquarium light forever, so if anybody has any thoughts on this I'm gonna look into finding something more heat-proof to stick under there. I would naturally assume that less light would make them more comfortable, which would allow them to come out of the plants and structure, not the other way around, so does anybody have an explanation?

The next time your fish are all at the top, can you start filming, do the light-blocking thing, and film them responding? And then upload the video to youtube and post the link here? It's not that I don't believe you, it's that I want to observe it for myself.

The next time your fish are all at the top, can you start filming, do the light-blocking thing, and film them responding? And then upload the video to youtube and post the link here? It's not that I don't believe you, it's that I want to observe it for myself.

Sigh. You ask too much of me. I'll see what I can do.

Sigh. You ask too much of me. I'll see what I can do.

If your light sits on top of the glass lid, you could attach plastic weed blocker to the under side of the glass. If you are not familiar with it, it's plastic landscaping fabric that has tiny holes that allow water to penetrate into the soil. I have a strip that sits on top of the glass in my light hood about 1.5" inches from the light and it stays cool. I don't know about temp ratings for it though.

Another option is plastic mesh from McMaster Carr. It is designed for grain/ag sifting and is tolerent of heat up to 260 degrees F. It is also sold in a variety of mesh sizes so you can control the diffusion of light. You want the molded plastic fine mesh.
Link:
http://www.mcmaster....ic-mesh/=9ld0mb

Yet another option could be to use fiberglass-poly screen that you can find at the hardware store used for screen doors and such.

Edited by GreenRiverKY, 05 November 2010 - 08:41 PM.

I would like to see this also. Ever thought it could be the fish reacting to you? I fish act differently when I'm/anyone stands near the tank.

What kind of lighting do you have? Incandescent, perchance?

NCNativeFish,
I don't recall your setup - are your plants live? Lowering the light levels may not be the best idea.