Danios Gone Into Hiding

[McCool]

So I have a 55 gallon tank that currently houses a brown knife, 6 Giant Danios, and a pleco who is going back to the store. Anyways, A few days ago I took the canopy off and rigged the set up with a grate over the tank so no one could jump out. After I did all that, the Danios just disappeared. This was a few days ago, and I just got the Plec and Knife today, and they seem fine, but the Danios are still hiding! I can find a few of them hidden around in various places underneath the rock, but they won't come out. There are two small ones that have come out a few times, but other than that, nothing. Temp is around 76, Nitrate is pretty much non existent, Tank is cycled. I did a 30% water change today just in case, but they still haven't come out. Any clues on what is going on? No one is acting sick, And before they went into hiding they all swam around the tank together and were eating with a vengeance. I'm pretty confused...
Anyone have any idea on what is going on?

 

[N0body Of The Goat]

The lack of a lid has made things too bright for them, perhaps? Many of my fish are "sun haters", oh the irony of my first tank (Rio240) having 110W of T5HO lighting which consequently rarely gets used!

 

[McCool]

Actually, I was able to rig it up with a grate under the canopy, so they couldn't jump out the back. The lighting is the same as it was when they where all swimming around happily. Honestly, nothing is different! In the beginning they where all racing around the tank and acting great. Hmmm. Maybe they will come out in a few days?

 

[McCool]

False alarm! They are all out swimming!