In my quest to finally have a tank I've decided on a shallow one. 48 long, 24 wide, 12 high. Does this in any way limit me to a certain fish size? Can I have a tang in this tank? I know my vertical scape will not be the same as a deeper tank but I think I can make it work.
I'm pretty sure I'm going to have the tank built so I could go a little higher on the height.
Thanks!
You've gotten some good feedback in this thread already. I'm going to share my experience. I have a 72"L x 24"W x 18"H. It's shallow but not as shallow as what you are considering. For me, the 18" depth is very nice for cleaning purposes. The height still allows for various fish zones, meaning it's deep enough that I can have some fish that hang out very high in the water column, some in the middle, and then I have those that stay near the sand bed. At 12" height, I think things would be more cramped and you will be a little more limited in your fish stocking.
In regards to lighting, the 18" depth allows for easier lighting. Honestly, though, it seems light intensity is hardly an issue as lighting fixtures seem to be so powerful nowadays. If anything, I think the shallow depth makes it harder to keep various corals that have different light needs. It's going to be hard to blast an acropora with 300 par and have lower light areas for softies or LPS for instance. If you're not interested in a mixed reef and going to stick with softies / LPS or just SPS, then this is probably not as much of a concern. Or if you're going to be using T5 lighting versus LED's, this may not be as much of an issue (I find some of my corals can tolerate higher par values from T5 than they can from LED's).
If you're going to have a sand bottom, you're going to need smaller pumps. My MP40's I have to place a few inches below the water line so that they do not suck air into them, but if I set them too low, they suck sand up into them. If I had a 12" height, I suspect I'd have to run my MP40's at half the power I am running them at now (or go bare bottom).
When you're getting quotes, your tank manufacturer is most likely going to be using 3/8" glass or 1/2" glass. They should have guidelines they use to determine the maximum height before they need to increase to a thicker glass (assuming this is a rimless tank). The thicker glass is what will increase your overall glass cost. My point, though, is that if they are quoting you using 3/8" glass, they may just as easily be able to go from 12" to 15" or even 18" without much additional cost as may be able to stay with the same glass thickness. , iMy tank is 1/2" thick glass, rimless, and the person who made my tank wasn't comfortable going over 18" or so in height without going up in glass thickness. Extra height will add more stress to a rimless tank than extra width or length.
Assuming you have space and don't mind needing extra lighting, I would recommend getting as WIDE a tank as you can. Length would be my second preference. Height is my lowest on my list. In my case, the 18" height has worked well. I would be fine with as high as 21" but I would not want much shallower than I have now. I really wish I had more room so that I could have gotten a 3 or 4 foot width, though! The 6 foot length has been great, and is day versus night in comparison to my previous 4 foot long tank in regards to the swimming area for fish (especially tangs, which I also keep).