enough light for squamosa?

[jjz_13]

Hi. Was hoping some clam experts could give me their opinions on lighting.

I have a 150 gallon tank (72" x 18" x 29"h).
I would like to put a clam on my sandbed and was thinking a squamosa would be nice. (i.e. bury a flat rock below and let the clam attach to it)

I'm not worried about my water parameters - they're all good, but it's tough to find a definitive lighting scale for clams.

My lights consist of:

3 250watt 10K metal halides
2 96watt actinic power compact flourescents (each 3' long)

The lights are all spaced evenly, with the MH's in the rear of the hood and the PC actinics in the front. They are all mounted about 12" above the water surface. My sandbed is about 4" deep.

The tricky part is that I don't run all these together most of the day because of heat concerns. I cycle the MH's throughout the day starting on the right side and ending on the left. The following schedule helps keep my tank temp b/n 80-82 degrees.

9am: Both actinics ON
10am: Metal Halide 1 ON
12:22pm: Metal Halide 2 ON
2:45pm: Metal Halide 3 ON (all lights are ON at this point)
3:15pm: Metal Halide 1 OFF
5:37pm: Metal Halide 2 OFF
8pm: Metal Halide 3 OFF
9pm: Both actinics OFF

Is this sufficient for a squamosa on the sandbed? How about a maxima somewhere on the rockwork?

Thanks in advance for your advice.

 

[Jeffrey Porter]

I think that should work for a squamosa. I just have 2 130w actinics and 2 150w 10K's on my tank, but the halides run from 11am to 7:30 pm.

 

[mahoneyc3]

you can do any clam with that, the 250 MHs are going to be great, most likely even a Crocea on the sand, IMO.
its always a good sign to listen to the animal when its trying to tell you something though. if its really reaching for the light, that means move it up, youll know what it looks like when you see it.

 

[JR719]

Yep, you'll be fine with a squammy.

 

[a4twenty]

definitely any clam with 250 MH's, not sure about a crocea on the bottom of a 29" tank but a squamie for sure.

 

[jjz_13]

Thanks everybody for your input! To be greedy, a couple more questions...

I think I've read that the Squamosa can reach up to 18" in length. In your experience(s), how fast do they grow and will they actually get that large in an aquarium?

 

[jmaneyapanda]

squammies do grow quick and do get big. I know this firsthand.

I have a comment on your lighting scheme. I would recommend a greater duration for the halides. At 6', a 250 bulb at one side will not light very far on the horizontal axis, especially at 29" deep. So, each bulbs should probably be run a bit longer since each "quadrant" will likely only really benefit from the bulb directly overhead. It looks like you have about only 5 hours of light per quadrant. That MAY be enough, but I would bump it up a little, to 7 or 8. I happen to run mine for a good length of the day. You'll spend more on the electric bill, but the animals will be happier. just my 2 cents.

 

[jjz_13]

thanks, jmaneyapanda - that's exactly what I was concerned about. The problem is - if I run them longer than I do now, my temperature also gets higher. Right now it maxes out at about 82. I guess I could experiment and see how high it gets, but I'm starting to get out of that comfort zone past 82.

One thing - I plan on putting the clam pretty close to the center of the tank. Does that help me in your opinion?

 

[jmaneyapanda]

Hey Joe- heat is a concern, but there is a very easy fix. and it'll cost you less that $50. Get a fan, and run it across the water surface. In the sump, across the top, whatever. It takes a termendous amount of energy to turn water from liquid to gas. When your tank does this, that energy comes at the cost of heat. It will require more attention to topping off, but will definitely cool off the water.

I would also be concerned about temps at or above 82. In regards to placement, do you mean in the center on the horizontal or vertical axis? I still dont think you'll get much horizontal assistance from the other lights. I have 2 20 and a 400 on my 210 (72X24X29), and the 400 is in the center, and turns on after the 250s and off before the 250s. When only the 250s are running, the center is not lit very well. I havent measured PAR, but I can see the actinuic glow, which is telling me a lot.

 

[jjz_13]

Sounds so simple, doesn't it?

Yeah - I'm using fans already. One blowing across the water in the sump, several in the hood. I lose a lot of water in the process, but have an RO/DI auto-topoff that keeps me in check.

I guess I have some thinking to do... Maybe the clam isn't a good idea unless I start using a chiller.

 

[jjz_13]

Oh sorry - I didn't answer your question. I mean center of the tank on the horizontal axis.

 

[jjz_13]

BTW - great pics in your gallery...

 

[Jeffrey Porter]

During the summer i put a 16" fan next to my tank, and it can drop the temp by 3-5 degrees before i get home from work.
It ends up cooler at the end of the day than before the lights even come on.