Venturing Into The Reef World...

[eschaton]

I'm strongly considering entering the reef world within the next month or so, though due to a planned move this summer I'm going to set up a "temporary reef" for the time being with existing equipment mainly to mature rock and a deep sand bed. By the Fall I plan on having a dedicated reef system.

While I realize they won't work in the long run, I wonder if my freshwater plant lights will be good enough for a short-term tank. I have two Coralife plant fixtures. Each has a 14 watt full-spectrum bulb, and 14 watt 6500K bulb. Altogether, this comes to 56 watts, or 2.8 watts per gallon (going onto a 20-gallon).

I know the spectra is totally off, but it's my understanding that with such a comparably low wattage, the only photosynthetic inverts I could stick in there would be mushrooms right? Would the coraline algae mature on my tank? Why is it when plants grow quite well using these lights they're far too dim for sea life?

 

[SkiFletch]

Its not a matter of being too dim, its just a matter of what corals and their symbiotic zooxanthellae algaes are genetically and evolutionary designed to do. Remember, as you go deeper under water, Red, orange, yellow, and green wavelengths are eliminated. I dont know bthe exact stats but I do know that once you get down in the 30 foot deeper or more water, pretty much all red, orange, and yellow are washed out, and the deeper you go the only wavelengths left are blue and purple. That being said, organisms living deep down on reefs are designed to use those wavelengths and therefore corals will respond better to such wavelengths.

6700k lamps are very red compared to what most reef aquarists use. While this will be OK for shallow-water corals such as leathers and mushrooms, I'm not sure how calcerous coraline algae will react to them. My gut instinct is to say that the coraline probably wont die under such lights, but dont expect it to grow, especially if you cannot maintain high alkalinity.

 

[eschaton]

Thanks for the reply. Replacing the 6700K bulbs with bulbs with a better spectra should be within my budget, though an entirely new fixtures/a new tank isn't. I suppose using the 10,000K bulb and the actinic is what's needed. Would I need to get a Coralife T-5 series bulb, or would any old bulb of the proper size work? Could a higher wattage fit into the fixtures?

As to PH, my assumption was with live rock and live sand your PH is naturally basic - no need for any further buffering. This isn't the case?

 

[SkiFletch]

For bulbs you'd probably want a pair of these

As for pH, that is the case under ideal conditions which almoast never exhist. Calcerous organisms will use up Calcium and Carbonate (alkalinity) over time and the pH will drift downwards unless significant and frequent water changes are performed. In a nano tank, maintaining pH and chemistry is somewhat straightforward in that water changing is easy. Gets a little more dtricky in larger tanks

 

[eschaton]

hrrm...those bulbs certainly look powerful enough - and they are within my budget, but I'm not clear on if they'll fit into my existing Coralife fixtures, which take 24 inch 14 watt T-5's.

 

[SkiFletch]

hrrm...those bulbs certainly look powerful enough - and they are within my budget, but I'm not clear on if they'll fit into my existing Coralife fixtures, which take 24 inch 14 watt T-5's.

Whoops, read your post wrong, you need 14watt lamps?

 

[SkiFletch]

If I were you, I'd contact Coralife directly and ask them where to purchase marine spectrum bulbs. They sell that exact fixture with marine bulbs so somebody makes them

 

[eschaton]

I've actually already found two of the correct bulbs (though I cannot find another two). It seems like I cannot get more than 14 watt bulbs in a 24 inch dual T-5 unit though, so even with improved spectra I'm not going to do better than 56 watts.

 

[SkiFletch]

I've actually already found two of the correct bulbs (though I cannot find another two). It seems like I cannot get more than 14 watt bulbs in a 24 inch dual T-5 unit though, so even with improved spectra I'm not going to do better than 56 watts.

Yeah, without retro-fitting the fixture your options are limited

 

[ox5477]

Its not a matter of being too dim, its just a matter of what corals and their symbiotic zooxanthellae algaes are genetically and evolutionary designed to do. Remember, as you go deeper under water, Red, orange, yellow, and green wavelengths are eliminated. I dont know bthe exact stats but I do know that once you get down in the 30 foot deeper or more water, pretty much all red, orange, and yellow are washed out, and the deeper you go the only wavelengths left are blue and purple. That being said, organisms living deep down on reefs are designed to use those wavelengths and therefore corals will respond better to such wavelengths.

6700k lamps are very red compared to what most reef aquarists use. While this will be OK for shallow-water corals such as leathers and mushrooms, I'm not sure how calcerous coraline algae will react to them. My gut instinct is to say that the coraline probably wont die under such lights, but dont expect it to grow, especially if you cannot maintain high alkalinity.

On a side note about the diminshing of color spectrums as you go deeper.... its def pretty cool watching something on animal planet or the discovery channel about deep sea fish and how they glow red in our light. Such a cool adaptation they have. It is just another amazing reflection of how evolution really picks out the best features and makes them flourish. Nature is just so cool and fscinatiing!!!

sorry to get off topic...