Why do my fish hide when lights turned on?

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Aquarium Advice Newbie
Mar 17, 2010
Portsmouth, UK
Hi there

I have owned a Fluval Vicenza 180 aquarium for 10 days and each time I turn my lighting on, my tiger barbs, angel fish and silver dollar all go and hide away from the light...???

Its very dissappointing as I stare at what looks like an empty fish tank. My tank is second hand and the filter is mature, that is why I was able to transfer my fish across so quickly.

Any ideas why? Any solutions? Any Fluval Vicenza owners out there?

Thanks in advance

Is there any decor for cover? Plants?

I always hide under the covers when the light is suddenly turned on. ;)

Welcome to AA!
YEs - there are rocks and bog wood for them to hide under - thats why I cant see the little monsters unless I am a foot away from the tank and then can watch them all huddled for cover!
try turning on a lamp real close to the tank for 10-15 minutes before you turn the tank light on. in nature, the sun doesnt suddenly pop up and shine, it slowly comes out. If you dont replicate this, sometimes it can scare the fish and they hide from the shock
Also, it may seem counter-intuitive but the more cover that shy fish have, the more you will see them.
Do you have a timer for the light? I'm wondering if you standing there - this huge dark shadow looming, and turn the light on by hand can be scaring them too. Most use timers. Try that so that they stop associating the light being turned on with the huge monster standing outside of the tank.
you could also try feeding as soon as you turn the light on... if the light comes on in my 150g, my fish are begging for food... its just natural for the light to come on at a certain time and go off at a certain time in my planted tanks...
yes mine do the same. The food drops within 30 seconds of the light being turned on. The newbies take a few days to put this together but they catch on. When I turn the light on they all rish to the top. If I forget to turn it on, they practically bang on the glass to get my attention. Sometimes I do startle them and they hide for a while, but they always come out. The feeding thing is kinda like Pavlov's dogs, they will catch on to the routine :)
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The first morning after I got my two clowns I flipped on their light at 4:30 am...Let's just say I'll never do THAT again :) They sleep in to at least 7:00.
I agree with everybody else. I turn my lights on when I get up, and I wait about a bit (15-30) mins before I feed them. Some of them hide when the light turns on, and I like to let them come back out. After about 5 minutes they're all at the top waiting for food from the "big shadowy monster" ;). They're so funny.
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