Fish Acting Odd/stressed?

[mwood2]

Well I made a few changes to my tank recently, mainly in the form of a powerhead. I bought an AquaClear 50 Powerhead with the hopes to add some water movement and aeration to my tank which normally stands still. The current setup is:

29 Gallon:

Eheim Ecco 2234 (rated for 60 gallon)
Aqua Clear 50 powerhead

6 Harlequin Rasbora
1 keyhole Cichild
1 Opaline Gourami
1 Platy
1 Upside-Down Catfish
1 BN Pleco
7 Kuhli Loach

I have not seen much agression besides the occasional chase caused by the opaline but it never seemed that bad. Once I added the powerhead everything seemed to go downhill. The current didn't seem to bug anyone at first but after a day the keyhole seemed extremely stressed so I unplugged the powerhead for a bit and everything seemed fine so I tried it again but this time I pointed it more to the back wall. Came home from work last night and the keyhole was stressed and very discolored like before so I shut off the powerhead right away. Since then I have noticed the Keyhole has remained stressed, the platy is hiding and the opaline seems very timid. Everyone else is fine from what I can see. Also did a test for ammonia and nitrite and everything seems perfect.

Anyone have an idea of what might be wrong?

 

[KittyKat]

You should not have needed a powerhead on that tank.. there is nothing wrong with low circulation: traditionally, freshwater aquariums can do with as little as 2×. You have not said what your combined water flow is between filter and pump? It could just be that it is too strong.. it does depend on the layout of your aquarium, of course.

 

[mwood2]

well the output of my ecco has slowered and while it filters just fine the water just doesn't get moved a whole lot thus I figured it would add some extra aeration and movement, I didnt think the flow was that strong once placed against the back wall of tank. Its been off for a few hours now but not much has changed at all.

 

[KittyKat]

If a fish is stressed, it may take some time for it to recover.

Have you tried having the outlet from the filter on one end of the tank and the inlet on the other?