At What Times Should The Lighting Be On Above The Refugium

In the refugium we are attempting to grow macro algae. The reason for this is that as they grow they remove nutrients like nitrate and phosphate out of the water.

In a previous post I have discussed what type of lighting should be used so that you can get optimum algae growth plus I have also talked briefly about harvesting the algae from time to time.

One thing which I have not really touched upon is how long you should provide lighting for.

There are two methods available – one which I agree with and one which I don’t.

I shall cover the one that I don’t agree with first.

Option 1 – Provide Lighting Over a 24 Hour Period.

So why don’t I agree with this?

Basically it’s because it does not happen in nature. There are some aquarists who believe that providing lighting over a 24 hour period prevents algae crashes from happening. This is where all the algae suddenly dies and all the nutrients which are removed are released back into the aquarium.

To me this has never been proven. If you look at nature the algae beds in the sea are exposed to sunlight over a determined length of time. The same as provided for the corals. You would not leave your lights on for 24 hours to provide light for the corals so why do it for the algae.

I am firmly of the opinion that we should attempt to replicate nature wherever we can. It works in nature so why try to change it in our aquariums?

I also believe that the algae needs a rest!

There is another factor to this as well. This is that in darkness the micro organisms come out more and start to feed and reproduce. It has been noted by many aquarists that they have experienced a pod explosion when the lights are out for a length of time.

Option 2 – Provide Lighting Over A Shorter Period.

This is my preferred option.

I have covered some of the reasons above. i.e. lighting is not provided over a 24 hour period in nature so why do it in our aquariums and the factor of the little critters which we are providing refuge to.

So how long is a shorter period. Well it can be many things but the method I use is that the lights above the refugium turn on when the main lighting turns off above the display aquarium – i.e. the metal halide lighting. They stay on all night and turn off when the metal halides turn on the next day. This is sometimes called reverse sunlight lighting.

So why do I do it this way and not have them on at the same time as the metal halides?

Basically this is so that I do not experience a drop in pH over the nightime hours. The reason this happens is that when the lights are on photosynthesis occurs, carbon dioxide is used and oxygen given off into the aquarium and the pH rises or in this case remains stable.

Stability as we all know is a major factor we are all hoping to achieve.

If we had the refugium lights on at the same time as the main display aquarium when all the lights went off there is a possibility that the pH will drop.

So that’s why I prefer option 2 – it simply makes sense to me.

Another thing that I also do is occasionally turn off the lighting above the refugium for a couple of days. I have found that when I do this I get a lot more ‘critters’ in the refugium. The more ‘critters’ there are the happier I am!

---

Related Posts

• How Long Should You Leave Refugium Lights On For Refugiums are becoming more and more popular nowadays as people are starting to realise the beneift that they can have upon the aquarium. Refugiums, as...
• The Aquarium Refugium A [tag-tec]refugium[/tag-tec] (or a fuge as they are commonly known) is a small aquarium which either sits next to, hangs upon, is below the aquarium...
• Aquarium lighting for reef tanks. A topic that is not discussed very often is [tag-tec]aquarium lighting for reef tanks[/tag-tec]. Although this topic is not discussed very much it is very...
• Should You Use Cured Or Uncured Live Rock? Live rock has become a widely used media for filtration. It is a natural way to filter and it deals, within reason, with the full...
• Cryptic Zones Can Be As Interesting As The Display Aquarium Cryptic zones really interest me. Of course everything in relation to this wonderful hobby is of interest to me but there is something about life...

Related Websites

• The World Is Watching People often get into the idea that they are "entitled" to do what they are used to doing, and get deeply stuck in their habits...
• Why In The World Do Businesses Leave Their Lights On At Night? I had to run out and do some errands late last night and I was amazed that every single office building I drove by had...
• 4" Clear / Amber LED STT Truck Trailer Boat RV Light Product Description4" Clear / Amber LED Stop Tail Turn LightLens is Clear, Diodes are AmberRound, sealed waterproof LED lamp for Trucks, Trailers, RVs, Boats and...
• Decoration Of Corridors A corridor can be an area a little tricky to decorate. If you want to better organize such a small space like this do not...
• There Will Be No Change Without Any Effort. In past articles, I have written about how changing a light bulb won't fix everything but also that the little things do matter when added...

Tags: Aquarium Filtration, Aquarium Lighting, Equipment, macro-algae, marine-aquarium, refugium