Lights off - any harm to fish

brett559

New member
Is there any harm in leaving the lights off for a month? My new tank is just getting started; I've got two chromis in there right now. I've read that to limit algae blooms in a new tank it's a good idea to leave lights off for a month. Does that really help with algae? Does it harm the fish at all?
 
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Doesn't harm the fish in any way. With ambient light from the room and/or sun it will mimic cloudy days in the ocean
 
Is there any harm in leaving the lights off for a month? My new tank is just getting started; I've got two chromis in there right now. I've read that to limit algae blooms in a new tank it's a good idea to leave lights off for a month. Does that really help with algae? Does it harm the fish at all?

I wouldn't say it's a good idea.....it's an idea. Algae blooms are part of the cycle a new tank goes through, almost everyone gets it when starting out, just one of those things that comes and goes as your biofiltration works itself out. In severe cases of GHA I have heard of people cutting lights for a period, however not as a preventative measure.
 
If there is going to be an algea problem in a new tank, leaving the lights off for the first month would only delay the algea problem for a month
 
The best way to fight algae blooms is with competition. Algae engage in chemical warfare just like corals. So you want desirable algae to get the upper hand. My algae of choice are coralline algae

First get a good algae control crew. Turbo-snails and hermits worked well for me.

Next, add some pods - tigger pods work well for a fresh tank without competitive species like Amphipods or Mysis. Those guys will also help you keep algae in check and provide food for fish.

Feed lightly and do aggressive water changes to keep nutrient levels low.

Start dosing 2 part calcium & magnesium and add enough coralline seeds like encrusted live rock or scraped off, crushed coralline from another tank (best source is coralline encrusted equipment - a good LFS should be able to give you some) to get them growing.

To promote coralline even further you can also reduce the white component of your light and only leave the blue on.

Lights (completely) off won't solve your problem long term but could rather make it worse as nuisance algae are usually hardier than everything else in the tank. So with making it even harder for their competitors you will actually give the nuisance algae an advantage.

At some point you may also want to set up a little refugium/algae scrubber with chaetomorpha.
 
Won't harm the fish... but there is a reason you have algae...

It's really just a temp. fix...
 
My plan is to do 20% water changes for three weeks, then on the fourth week do a bigger water change, testing my levels each week. Then try the lights after the big water change.
 
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