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Lights On or OFF during cycle?

51K views 22 replies 8 participants last post by  hackshobby 
#1 ·
hey everyone, I am in need of some input from the vets out there..
I recently ( 10 days) set up my 55 gal tank, and I was already starting to see algae growth, like lime green color and some diatoms. However I knew my tank couldn't be done cycling, but I tested anyway and had my LFS test as well, and go figure, its not. so, I assume it is my lights that is sparking the new growth? but, I have read on here that some people like the lights on, and some people like them off during the cycling process.

My question is, should I leave them on or off?? If I leave them on, and the algae continues to grow, what could I do to combat this?
Thanks
 
#2 ·
On.

Then suck out all the brown alage that forms. It will drastically reduce your phosphate cycle (a thing that can take up to a year to clear up).

Since you have no bioload, you have the oppurtunity to export all the built up nutrients in your Live rock whilst adding none. after your first fish, things become harder.

Oh and welcome to TRT!
 
#3 ·
On.

Then suck out all the brown alage that forms. It will drastically reduce your phosphate cycle (a thing that can take up to a year to clear up).

Since you have no bioload, you have the oppurtunity to export all the built up nutrients in your Live rock whilst adding none. after your first fish, things become harder.

Oh and welcome to TRT!
OK, so then to suck it all out, that would also imply water changes during a cycle right?
 
#4 ·
I have to disagree.

During the cycle you're trying to grow bacteria. Algae utilize many of the same nutrients as the bacteria you're trying to grow. This creates competition, and can reduce the speed at which the bacteria grow. If you keep the lights off, you do away with this competition, and the bacteria get to use all of the available nutrients.

In a new tank set up there should be very little phosphate to worry about. Unless you're curing LR with the cycle. Very few people do that any more. The little phosphate that is in a new system, is needed by the bacteria.

There's no need for water changes during the cycle either. You need the nutrient levels to climb so they'll fuel the bacterial growth. Changing water reduces nutrients and is counter productive.

Peace
EC
 
#7 ·
I have to disagree.

During the cycle you're trying to grow bacteria. Algae utilize many of the same nutrients as the bacteria you're trying to grow. This creates competition, and can reduce the speed at which the bacteria grow. If you keep the lights off, you do away with this competition, and the bacteria get to use all of the available nutrients.

In a new tank set up there should be very little phosphate to worry about. Unless you're curing LR with the cycle. Very few people do that any more. The little phosphate that is in a new system, is needed by the bacteria.

There's no need for water changes during the cycle either. You need the nutrient levels to climb so they'll fuel the bacterial growth. Changing water reduces nutrients and is counter productive.

Peace
EC
I had read similar theories before and that does make sense, I would prob do it lights off next time. I had lights on throughout my cycle. I was trying to "get the new tank algae blooms out of the way" during the cycle. But your tank has to readjust anytime you add anything anyways so when it is young you will have small algae blooms a few times, as you add livestock, regardless
 
#11 ·
No worries. There are many valid arguments to both. I start with uncured LR in my tanks and I use the barren period as a method to export nutrients stored in the rock.

Another option I've used is to cure in the dark (lights off) and run a phosphate remover (like RowaPhos) to clean up phosphate before it has a chance to grow into alage. Bacteria still get their fair share (at least they did in my situation).
 
#8 ·
Why would they get an algae bloom? Where are all the nutrients coming from to fuel this algae bloom? Keep things clean and don't stock to fast, and there'll be no bloom.
 
#15 ·
Thanks for all the feedback everybody! I am going to leave the lights out for the remainder of the cycle, and just remove what algae I can find. hopefully what EC said will happen, that by not stocking too much at one time and keeping stuff clean will help a lot. :wavey:
 
#18 ·
I run lights on during cycle, I don’t believe lights out to be an effective way to eliminate unwanted algae or affect the bacteria , I have always ran them during the cycle for as long as I been keeping marine tank. I may run them for a shorter period and now since LEDs, not as intense.
 
#23 ·
Welcome to TRT Michel! Amazing how our hobby has grown and changed in the past 10 years. ROCK SOLID BELIEFS have been shattered......technology has taken lighting into the WOW zone......and the things we can keep alive now is INCREDIBLE!

Looking forward to seeing your return to the hobby,
Hack
 
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