Stressed fish

[sid014]

Hi
I recently built a tank which is only 10 days old. I cycled the tank with bacteria in a bottle and fish food flakes and I added 5 cardinal tetras and 2 guppies in my 10 gallon tank. I have driftwood and a stone along with 7 Amazon sword stems, a java fern and a species of plant that somewhat resembles a cryptocotyne(i dont know which plant it is).
The ammonia is at 0.5mg/L and I lost a tetra today in the evening. My concern is whenever I switch on my light or switch it off the 4 cardinal tetras left in my tank and guppies really get stressed out. The cardinals break the school. Although they might be roaming with one another when the lights are on but as soon as i switch them off, they run like hell and break the school. They wander off alone and get really agitated. I don't seem to understand the reason behind this.

I want to ask that is this behaviour normal or not. Should i be concerned about this behaviour.

PS: i switch on my tank light at 12 noon and switch it off at 8 pm. I have really bright light with white red and blue leds.

Any help is appreciated.

 

[PheonixKingZ]

If you take that much precaution, then I would say the light is not to blame.

 

[Colin_T]

Stress from tank lights coming on when the room is dark can be an issue. Fish don't have eyelids and don't tolerate going from complete dark to bright light (or vice versa) instantly.

In the morning open the curtains or turn the room light on at least 30 minutes (or more) before turning the tank light on. This will reduce the stress on the fish and they won't go from a dark tank to a bright tank instantly.

At night turn the room light on and then turn the tank light off. Wait at least 30 minutes (or more) before turning the room light out. This allows the fish to settle down for the night instead of going from a brightly lit tank to complete darkness instantly.

If you put some floating plants in the tank, it will help reduce the lighting stress on the fish.

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You also need to do a 75% water change and gravel clean the substrate any day you have an ammonia reading over 0.

 

[seangee]

Cardinal tetras don't like bright light. They naturally occur in forested areas so there is a lot of shade and the water is usually stained dark by the wood - you may come across the term blackwater fish (please note this does not mean its dirty). If you are able to dim your lights you should do so.

I don't keep guppies, but in the wild tetras occur in groups of hundreds or thousands. When they are in a tight bunch it is because they are stressed and do this to feel more secure. They will spread out more once they are relaxed. You could use floating plants to filter the light. Frogbit and water sprite are both good choices for this.

This tank currently has 29 cardinal tetras in it (Its quite a bit bigger than yours though ). You can see what I mean by the floating plants - the lights are on as bright as it ever gets. As you can see my cardinals are not shoaling tightly, but that is because they are not stressed.

 

[sid014]

Thnx for the help. Can duckweed be used as the floating plant? And my tetras were shoaling tightly so i think they were stressed.

 

[Byron]

Thnx for the help. Can duckweed be used as the floating plant? And my tetras were shoaling tightly so i think they were stressed.

Duckweed is not going to be of much help when it comes to blocking overhead light because being so small it does not block much light. Substantial floating plants are better (ideal), such as Water Sprite, Frogbit, Water Lettuce, and some stem plants do well left floating (pennywort, wisteria).

The advice from other members concerning light was accurate, this is a major issue for most tropical freshwater fish because they occur primarily in very dimly lit waters.

 

[seangee]

Yes you can use duckweed. Be aware that its hard to get rid of if you choose to do so later. The more substantial plants I mentioned will also to more to help with the ammonia problems you mentioned in your other thread.

A few months ago I moved all the plants to one side of the tank using a piece of rubber tubing to hold them there. In about 4 hours not a single cardinal tetra went into the area that wasn't covered over, which was when I decided to let the plants go mad on top so they are always under cover.

 

[Colin_T]

Can duckweed be used as the floating plant?

yes