tko187

Hi guys this is my first post, hi to all!! I used to have fish a while back but its been about 6yrs now, I have just set up my 3 1/2ft freshwater tank up.
Just wondering if you could help, my new fish which are 3 days old in the tank are looking good, the only worry i have is the neon tetras seem to stay at the back of the tank, (i have a black background) also the same with my silver sharks, although they seem to be coming out a bit more now, when the light is turned off they come straight out to the front of the tank, is there a reason for this, if any one can help i would appreciate it. I currently have 10 neons and two silver sharks. pls help!!

COBettaCouple

Welcome to Fishlore.

If you're cycling a tank with fish, you'll want to change at least 25-40% of the water daily and use a water conditioner called Prime.

Tavel

The fish might just be afraid in their new environment...or afraid because the lights are too bright.

Either way, you can try dimming the lights by putting thin strips across the lid to block the light in a uniform pattern. maybe 1/2" wide, and spaced 1/2" to 1" depending on how much light you want to block.

It works somewhat like closing the window blinds part-way. It will work very well if the light is fluorescent, little heat and unidirectional light output. If the light is incandescent, you should use metal strips (like aluminum from pop cans...) and there might be small shadows cast in the aquarium because incandescents give off directional light.

you could also get lower wattage bulbs...but it's not very clever to spend money if we don't even know if that's the problem.

A final advantage of dimming the lights is that algae has a really hard time growing. Only brown diatoms will grow, and you can wipe those off with your fingers every once in a while.

I have the lights dimmed on my 20G aquarium, the fish seem to like it.