too much light a problem?

[grizz99]

i have a 75 gal tank that i was gonna order a light setup for real soon. my question is if i have 2-250 watt HQI MH and 2-110 watt VHO's would that be too much light? i plan on having them 10-12 inches above the water surface. this works out to about 10watts/gal, is that too much? i plan on keeping all different types of coral and anything that i find interesting. i've heard people say you can never have too much light, and i've heard that too much light can be bad, please help me before i order the lights and can't go back.
ben

 

[Anonymous]

As long as you can control the temperature due to the heat of the bulbs, no light is too much.

 

[grizz99]

i was gonna have a fan blowing over the sump and the house stays at a pretty constant 68-72 degrees. plus the fans for the lights. do i need more to keep it cool?

 

[Anonymous]

For some people the fan is sufficient to keep the tank cool with MH via evaporative cooling, but that is not always true for everybody. YMMV.

 

[ADS]

Most HQI DE bulbs are in a pendant or fixture which helps dissipate heat. That is an excellent choice of lighting for that tank IMO.
That lighting will give you the versatility of keeping a full array of livestock. Be careful with soft corals and some LPS. These do not like direct MH light. Simple aquascaping will fix this problem by creating areas of indirect light for your corals.
Good luck.
Adam

 

[Anonymous]

The heat that many have to cope with is radiant heat from the bulb as IR radiation. Even if you cool the bulb with a water jacket to get it to be 70F, the IR radiation will heat up the water to some degree.

 

[Carpentersreef]

Actually, you can "overlight" an aquarium. Watts per gallon doesn't mean anything, because you can get varying quality of light bulbs in varying wattages.

Corals exposed to too much light can suffer from oxygen toxicity, which is BAD. :wink:
Decide first what corals you want to keep, and then provide the best environment for them.

Have a look at "Types of artificial Lighting" pg 331 - 332 in the book Aquarium Corals Selection, Husbandry, and Natural History by Eric Borneman

Mitch

 

[grizz99]

i don't have that book, so i just ordered it on amazon and will get it by christmas. what types of corals would that be too much light for? how much light would you recommend in my 75 gal tank so that i can get anything that i want? thanks

 

[Anonymous]

Low light coral such as some mushroom, polyp. LPS and softies may not like the bright light too much.

 

[grizz99]

well would there be a better lighting setup that would enable me to keep all the different types of stuff? if i went with 2-175 watt HQI MH and 2-110 watt VHO's would that still be enough light for the ones that need high amounts of light?

 

[Anonymous]

You can always put coral in a shady spot, or have the light in one side of the tank only. It is hard to judge from your setup, but my guess is that it is fine for most of the high light corals esp. if you mount them high enough.

 

[ADS]

I think you mean 150W HQI. The 175W bulbs have low PAR comparably in most studies. If you have the money to invest in the 250W setup there will be no need for later upgrades.
Careful livestock selection and placement are key. If you create indirect light areas in the lower parts of the tank you'll be set to keep most corals and clams.
Adam

 

[grizz99]

yea i think i'm gonna go with the 250's, i certainly don't want to have to upgrade in the future because that can be costly. i wish i had somebody locally who was experienced and could show me how to best arrange my live rock when i get it.

 

[Anonymous]

It is more of an art than anything that need experience. Do it yourself and see if you like the way it looks.

 

[Carpentersreef]

Good decision to get the book!

Keeping corals isn't just about light. All corals compete for space in one way or another - some via chemical means, some with sweeper tentacles, and some just simply grow over their nearest neighbour.
Create some shelves with your rockwork, and make sure that you have the proper water flow for each coral.

Also make sure that you acclimate your new corals to their new lighting conditions.

I would probably go with the 2 250's and only 1 VHO, with room to mount the other VHO later. You could put the bulbs on separate switches, too.

Set up your tank, sand and rockwork, and while it's cycling, read up on what you would like to put in it.

Good luck!

Mitch