Can new Lights make fish aggresive?

[sgtmet154]

I just installed new T5 Lighting on my 75 gal. Tank.
(6) 54W t5's - (3) actinic, (3) 10000k daylight.
I have (4) green chromis, and (2) clowns, an orange spotted goby, and assorted crabs and snails.
Since I installed the lighting, more than tripling my previous lights, the fish have become very aggressive towards each other. They had been in the tank together for over a month with no problems, but now they are chasing each other all over the place. I found (1) of the green chromis dead tonight. I got the lights because I want to get into corals.
:nopity:

 

[mettjl03]

I don't think lighting has anything to do with it... But I could be wrong... It may be from stress or even diet. Have you tested the water? Added anything new? or Have too many fish in your tank?

 

[Reddog170]

The lights may have coused a rapid algae bool and dieoff throwing your params out of whack and stressed out your fish. I would back down the lights for a bit, do a water change and test often. After having the lights down for a week or so then go back to full power or all light on and see what happens. Now please note that I am just speculating here. Keep us posted, Shaun

 

[BigAl07]

I'd test first and see where that puts us.

Also take note that those fish are all in the "Damsel" family *notice they all have the same general body shape* and are potentially going to become even more aggressive as time goes by.

Also note that even though fish don't "require" the light to thrive light does affect their behavior especially large changes. Maybe they're just not pleased with the sun suddenly being a LOT closer and brighter and are taking it out on each other. Also make sure the water temp hasn't increased because of the new light.

 

[sgtmet154]

:smack:
OK, I ran the tests:

Amonia: 0
Nitrate: 0
Nitrite: 0
PH: 8.2
KH: 240
GH: 180
Specific Gravity 1.0225

I have been missing my goby since Sat., not unusual since he hides in his hole a lot, so tonight I went in to move the rocks and find him, I ended up removing all rock from the aquarium and still no sign of him. I searched the sump incase he got into the overflow, and all around the outside of the tank and nothing. I have noticed that my skimmer has produced a lot of gunk in the last 24 hours which is unusal, so I am guessing he is dead under the gravel somewhere?

There are only 5 small fish (1 1/2" max each) in a 75 gal so I do not know why they are suddenly going after each other after getting along fine for over a month.

 

[Varga]

Maybe your tank was so dark before the fish couldn't see each other. Now, with the new lighting, they're like "holly cow who the heck are you"

 

[BigAl07]

Maybe your tank was so dark before the fish couldn't see each other. Now, with the new lighting, they're like "holly cow who the heck are you"

that's IT!

"Fool get outta My tank!"

 

[Dentoid]

That's an interesting observation to say the least! Did you notice an increase in temperature at all with the new lights? With increased temperature, comes increased metabolism.

FYI, your SG is a bit low for a reef tank. Shoot for 1.025-1.026 for best results with inverts.

 

[sgtmet154]

Very Funny, my wife agrees with you.

I am sitting here watching them now and 1/2 hour after I fed them it is like they are still fighting over food, I will feed them a little more and see if that settles them down.

 

[sgtmet154]

Thanks Dentoid,

The temp has stayed around 78-80, same as before. I will bump up the SG.

I do not have any corals yet, still getting tank fully set, which I thought I was until last weekend.

 

[mettjl03]

Maybe your tank was so dark before the fish couldn't see each other. Now, with the new lighting, they're like "holly cow who the heck are you"

Geez... how come I didn't think of that?? HAHAHAHA