Lighting For Hard Coral's?

[VictorMeldrew]

Hi all

Most of the advice i have come accross regarding lighting for hard coral's seems to suggest that if your set-up does not have MH's you have no chance keeping them. However i read an article recently that seem to say that many types of LPS and SPS do very well under lower level lighting and if i remember correctly some such as the sun coral (hard or soft coral, not sure?) actually prefer slightly shaded areas. What do you think, is it possible to have hard coral's under VHO T8's or T5 lighting?

Please bare in mind that i have not had a great deal of advice on this subject yet, so i could be talking complete rubbish

Thanks
VM

 

[1234-fishy-freind]

There is no doubt that hard corals do tend to need a greater amount of light than soft corals in the form of MH's but I think there would be certain species that could do well under T5's providing they were placed near them and fed.

But I have never tried to keep hard corals under anything but MH's so I dont have any real experience on the matter.

 

[Colin_T]

it doesn't matter if you use halides or fluoros as long as you have sufficient light getting to the corals. In tall tanks (say 2ft and more high) you need metal halides so the light can penetrate the deep water. In shallow tanks (say 12inches tall) T8 fluoros are fine.
I have kept Acroporas and other hard/ stony corals in my shallow tanks (12inches high) and they do well under normal T8 fluoros. I have 2 x 36watt globes over tanks that are 3ft long x 14 inches wide x 12inches high. The lights are actually 4ft long but they overhang the tank by 6 inches either end.
If you have a tall tank and want to use fluoros, then put the corals up near the surface so they get more light.
High Output (HO) T5s are better than normal T5s and T8s.

 

[xxBarneyxx]

Yeah pretty much what Colin said. It doesnt really matter what the light source is as long as there is enough of it. MH are recommended for most LPS/SPS just because to get the equivalent amount of light from T5's you would need a hell of a lot of them.

Some LPS such as hammers, torches and bubble corals will do fine under T5's (not sure about T8's, depends how many you have). I kept a hammer under 36w PC's and it did ok. Admittedly it would probably do a lot better under higher lights and since transferring everything to my new tank with more light I have noticed a massive difference in coral growth so while some corals will survive under lower lights you really need to have good light to make them grow well as well. Also some SPS will be ok under halfway decent T5 lighting if they are near the top of the tank.

Sun corals I believe are not photosynthetic (or if they are its not their primary energy source) which is why you have to feed them regularly. there are a number of other corals that are the same where the lights dont matter as much as long as they are fed.

Personally on your tank I would want to be using MH or good quality LED units (LED cost more to set up but over the course of a couple of years will be a LOT cheaper than MH). At least then you are completely free to stock with whatever you want and really make the most out of it.

 

[Colin_T]

Something I forgot to mention, but was reminded of by Barney.
The more light the corals get the faster they grow. However, the faster they grow, the more calcium they use and the more you need to monitor the levels in the tank. Therefore if you have lots of light the corals will grow fast but you will need to do more work in regards to monitoring the calcium levels and adding calcium supplements when required.

 

[SkiFletch]

Agree with the above with a few additions. T5 lamps can easily compete with Halides given one thing, that they have an individual reflector for each T5 lamp. Without individual reflectors, T5's aren't much better than their PC cousins and a lot of light is wasted. However when you have individual reflectors, T5's can even offer more punch than Halides. As mentioned, the difficulty is the complexity and expense of the system to setup cause you will need at LEAST 4 tubes to compete with halide setups, more like 6 to realistically provide the same light. Whereas on a tank your size Victor, you'd only need 2 halide lamps.

 

[VictorMeldrew]

Thanks for all the great info guys The only problem is that i think i am stuck with my T8'S at the moment and as you know my set-up is new and i really could not justify changing the lights so soon, the wife would kill me i really regret my opting for T8's now, as it turned out they were pretty pricey to, but i have to get on with it i suppose, so i will just keep getting softie's for now. I have 4 x 60inch 58w tubes so i still have a fair bit of light in there for them. Making wrong decisions from the get-go was something i really did not want to do but oh well you live and learn

Thanks all
VM

 

[BigC]

Vic, Life is all about making wrong decisions, its these wrong decisions that make us wiser.
If its any concellation....On this side of the hobby both wrong and right decisions invariably turn out to be costly.
Regards
BigC