Tiger barbs in hiding.

Berserker

Just want to get some opinions from people on the change in behaviour of my tiger barbs. I have 14 in my 180L and I introduced a crayfish about two months ago. The water has been changed and the tank has been cleaned on a weekly basis and the water parameters are all good, i.e. no ammonia, no nitrite and a small amount of nitrate. There is a some driftwood in the centre of the tank where the crayfish hides and the tiger barbs hide under the plants in the rest of the tank.

Over the past 3 or so days, the tigers barbs have been hiding under the plants in the evening when the light has been on. If I throw in food, when the light is on, they won't budge, with the exception of one or two of them. However, once I switch off the light, the all come out from hiding and eat away like savages.

I put some food in early in the morning, turning on the light in the tank first for a few mins, as it has been off during the night and they eat away with the light on at that time of day. I am confused as to what could be the source of this change in behaviour. Everything else looks good with them, no signs of bullying or fin nipping etc. They shoal when they are out and about.

kylith

Crayfish will catch fish if they can so it's possible that it's taken a swipe at one or two of them and they are now hiding from the predator in the tank. Make sure that you have lots of hiding places for the fish such as caves or lots of plants and the fish should feel more comfortable.

Berserker

Was thinking about the crayfish myself and I have this theory that the barbs know that it is active when the lights are out, so they are out and on their guard then but they also know it is in hiding when the light is on, so they rest at the point.

Berserker

Just remembered this thread and thought I would update it as it may be of value to someone else. So, it was the crayfish that was causing the change in behaviour. I re-homed the crayfish and within days the barbs were back to their usual fin-nipping selves.