I have a 160 litre community tank. I normally have no trouble keeping my fish alive. I have an eclectic mix of angels, gourami, various tetra, golden barbs and harlequins. Each day now for the past week, I have an average of 2-3 fish die. Normally they are neons but I recently lost 5 conchu tetras, a couple of golden barbs and a harlequin. Nothing has changed about my tank recently except the addition of a brand new and more effective filter. I do regular water changes and my PH levels are pretty normal.

Any feedback/ideas/recommendations would be gratefully received!

I'd say it sounds like perhaps your new filter has been the culprit.. perhaps an ammonia spike due to the removal of the previous beneficial bacteria colony which was inside the old filter.

Did you use any old filter media from your other filter, in your new one ?

Angels like to eat small fish. Could it be that? Or are you finding corpses?

I'd say it sounds like perhaps your new filter has been the culprit.. perhaps an ammonia spike due to the removal of the previous beneficial bacteria colony which was inside the old filter.

Did you use any old filter media from your other filter, in your new one ?

+1, I would put money on it being this.

+1, I would put money on it being this.

+1 again, take some water into your lfs and get the ammonia nitrite and nitrate tested

+1, I would put money on it being this.

+1

what happens to them / how do they act before they die?