SPS dominant shallow reef tank question

mp2022 · Feb 25, 2026

Hi all, I am looking for advice on a new tank which I am planning on starting in the next year. I currently have a 48 gallon as my first tank and am loving the hobby and watching my corals grow. Now that I have had an idea of what it takes to get tank going after many mistakes, I would like a bigger tank with the following goals:

1. Larger tank volume to accommodate broader range of fish. Specifically I would like either a yellow or tomini tang and maybe a coral beauty along with the six line wrasse, clown, royal gramma, and orchid dottyback I plan to transfer over from my current tank.
2. SPS and LPS corals - acros, montis, and euphyllia, acans, chalice, and blastomussa
I am looking seriously at shallow tanks, specifically 4 foot 75 gallon vs 5 foot 100 gallon tanks for the added length for the more active swimmers and ease of maintenance. I have read however that SPS options are much more limited in growth with the shallower depth (the tanks I am looking at are 15-16 inches deep). For those of you who have had this setup, did your acros/montis have any issues thriving? Is it best to just get a tank with standard dimensions if I want an SPS heavy tank?

This would be a final upgrade as I don’t have space for anything larger than a 100 or 120 gallon tank.

Thanks!

Tonycass12 · Feb 25, 2026

Will the corals have issues? Only if your rockwork is too high, not a ton of space for upwards growth unless you keep it short. I personally think 24"depth is perfect balance, keep the rockwork low and let the corals shine. Your shy fish and possible jumpers will do better in a slightly deeper tank.

But can it be done? Of course it can, you may just need to put a little more thought into fish species and aquascape in a more shallow display. Try keeping the rock in the bottom 3rd so the corals make up the middle depth in the tank as they grow in. Good luck with the new build!

X-37B · Feb 25, 2026

My old 80 48×24×16, which is actually 13.5" to the bottom. No problem growing acros. My new 112 is only 17" to the bottom.
The nicest thing about shallow reefs is the ability to work on them easily even if stand is 36".

mp2022 · Feb 26, 2026

Thank you both for the responses. Tonycass12, hadn’t thought about the verticality in terms of jumpers (I have a wrasse and like gobies). Glad to hear the shallow SPS reef can be done, X-37B. Tough call either way. Seems like 80-100g in general while a good size still significantly limits what you can do with stocking.