Is MH necessary in a shallow tank?

[dudeguy]

First let me qualify myself by saying that I don't have any clams, but I'm interested in getting some. I'm still in the "gathering information stage." I'm interested in starting a small tank just for clams.
I know most people with clams recommend metal halide lighting. If the tank is shallow and the clams are only 12" away from the light, is it really necessary to have MH?
Isn't it possible to get the same lighting intensity to a clam 12" away using VHO or T5 lights as it would be using a 250W MH bulb to a clam on the bottom of a 24" deep tank?
I'm interested in hearing your responses

 

[mantisshrimp]

I would still use MH,I have one and my tank's just 12" deep.

 

[dudeguy]

Thanks, but can you qualify your answer. Why would you still use one? Did you try VHO and notice that your clams didn't respond well with that kind of light?
I'm interested in people's experience with shallow tanks.

 

[clamster]

I'll re-read my bible on clams (by Knopp)
There's a chapter on PAR and PUR.
IME, my T. maxima wasn't too happy with 175W MH until I replaced it with 250W. And all this time, he was only 6'' from water surface.

T. derasa, however, isn't so light demanding.

 

[nvillacci]

I dont know...

I dont know...

But I had a Maxima in a 7 gallon bowfront with a 3 inch sandbed.
I had 2x36 inch PCs and he was doing fine...

So I think youll do fine if you have a shallow tank, just be prepared to move him if you see anything go south.

 

[dudeguy]

Thanks for the posts. I'll have to look for a book by Knopp.

I'm not trying to be as cheap as possible, I just want to understand what's required so I can be successful.
With that said, I am extremely suprised about the range of response so far.

One says 6" from the surface with a 175W mh isn't enough.
Another says 2 PCs in a 7gal is fine.
And both are maximas.

 

[mantisshrimp]

I have a maxima & squamosa.probably 4" or less from the surface of the water * or so from the halide.They're enjoying it.

 

[skull]

i will never use anything lower then a 250MH on any of my clams. don't matter on what size they are or how shallow the tank is. i've got a 58gal and my lighting on that thing is 1x400MH 20k and this weekend i will be adding 2x250w 65k on to it. so it would be

250x400x250
__ __ __
/ \/ \/ \

what ever you pick, good luck,souk

 

[clamster]

so the question is:
* enough light to keep it just alive
* enough light for the clam to find it acceptable
* enough light for the clam to be truly happy and thriving

For those who have successfully use VHOs on T. maximas, I wonder how my phytoplankton and what feeding frequency is used to compensate for the lower lighting.

I have heard of ppl keeping T. maxima without feeding phytoplankton for years and just scraping the algae off from the glass instead. Of course, they compensate for the reduced live food by using lots of light. On this note, I got to know if the diatoms scraped off from glass would pose some difficulties for the clams to digest or not. Oh well, back to Knopp's book of clams for me.

 

[skull]

it would be......

"enough light for the clam to be truly happy and thriving"

and not phyto feeding for me. i have clams that are as small as 1". they are really really babies