Clam lighting requirements

[zeblisik]

I'm setting up a 30 gal tank w/ sump(not sure how big it will be yet). The main tank is 12" high.

For lighting I'm planning on using PC/CF lamps:

- 4 x CF lamp, 6500k, 105 watt, 6720 Lumens
- 2 x CF lamp, actinic blue 03, 96 watt
- 2 x CF lamp, 50/50 10000k, 20 watt

I'm going to incorporate moon lighting aswell.

Is this enough so that I can eventually get a clam?

Someone recomended getting T5, in terms of light output are they any different than CF? I thought they were just slimmer and more efficient than the old T12s but not necesarily a better lamp than CF?

Also, since clams are more often from shallow waters, does that mean they are less dependant(for lack of a better word) on actinic lighting and better able to make use of a wider spectrum of light?

 

[mbbuna]

T5s are stretched out PC's. there advantage is the reflectors. PC's also lose there intensity fairly quickly, expect to change your bulbs at least every 6 months(if you want to keep a clam healthy and colorful). without MH lighting i would not get a Crocea or Maxima. Actinic lighting has little benefit for clams

 

[zeblisik]

thanks mbbuna, ive read a slew of your other posts about lighting, among other peoples; the advice is rather consistent.

when discussing lighting for clams, are lumens a good measure? (except that lighting for aquariums never list their lumens) The MHs ive seen have a lumens per watt ratio of around 80 in general. My CFs have a lumens per watt ratio of 60.

So as long as I supply enough intensity I could use CFs but the drawbacks are:
-CF dont keep their intensity as long as MH
-they're not as efficient intensity wise; mine have a lower LPW by 20
-and they take more space


I actually bought CFs not specifically made for aquaria use. But since they are mass produced and are 65k I thought they would be usefull to give the bulk luminosity for my aquarium.

 

[mbbuna]

i wish it was that easy. many things play into it.

http://hyperphysics.phy-astr.gsu.edu/hbase/vision/lumpow.html#c2

you also have to take into account that a MH bulb has all its energy coming from a single point and can drive that energy deeper into the water. with fluorescence that energy is all spread out, delivering less energy(in most cases alot less)where you need it

 

[Stephany]

I have a 30 gallon. I'm contemplating upgrading to metal halide for a future crocea that would love to make its home in my tank.

Currently have 2 75 watt VHOs... While it is 6 watts per gallon, I wish I had more.

Now all I have to decide if I want to scrap my new VHO ballast, and get a metal halide setup.
Wish I had gone that way the first place.

 

[zeblisik]

Stephany,

You can't really go by watts per gallon... different lamps produce different intensity(lumens per watt) and quality(different colour temp, say 3000k, 6500k 10000k) light.

hmmm by watts per gallon i have 21.7 watts to the gallon...

No need to scrap the VHOs, keep them and simply add metal halide. Get some regular bulbs(as opposed to those specific for aquariums) at 6500k.

Construct a new hood and add the VHOs w/ 2 metal halids in the middle. You can use actinic blue VHOs thereby supplying your inverts w/ the proper quality of light, and the metal halides will give you enough raw power to keep that clam you're dreaming of....

 

[zeblisik]

mbbuna,

ive thought about your reply somewhat. i understand about light going all about and the use of quality reflectors.

However w/ regard to MH light coming from a tiny area... I can only surmise that you're saying something like florescent lights are larger therefore it is more difficult to effectively reflect and direct their light. MH is small, therefore it is much easier to direct the light.

 

[Peabody]

Think of it this way. It's called "Point source" and what it does is really "punch through" and penetrate the power through the water. Drop a 500 piece of plywood flat into a pool. It might drop down a few inches before it starts to surface. Drop a 500 pound concrete ball into the water and it's going to punch down far through the water. MH bulbs vs. PCs are no different. MH really penetrates all it's energy through the water....it's not spread out at all.

In the end, it comes down to PAR. MH bulbs have significantly more PAR than anything else. Personally, I would never keep a maxima or crocea clam without MH light. I've seen way too many people lose clams under PCs....pretty much everyone I know who tried.