Need help with planning new tank

[arkodios]

I have been in the hobby since mid 2019. I got into saltwater in January and I’ve been loving it so much more than I thought. I love all the variability compared to freshwater. I currently have a Waterbox Cube 20 that has been nothing but as unproblematic and fun as can be. It did not go through an ugly phase and I’ve had a good time growing and stocking the tank. I am ready to upgrade. I am stuck between a 75 gallon tank (UNS 90U) or a 120 gallon (UNS 120U). This is going to be a unique tank for reasons that I won’t mention until the tank is well-established. My main concern is the expense; I am 17 years old and I have to pay for all my aquariums myself. I planned it out and the 75 gallon would cost me approximately $2000 and the 120 gallon would be about $4000, not including any livestock. I need some input on whether the 120 gallon will be worth it or not.

The 75 is 3 feet x 22 inches x 22 inches

The 120 is 4 feet vs 2 feet x 2 feet

The tank is going to be stocked with a lot of filter feeders (gorgonians, scallops, clams, macroalgae, sponges, etc…), acropora, anemones, euphyllia, and some others.

I would like to do a tang, as well as tons of gobies (including sand-sifting gobies, wheeler gobies, diamond gobies, and clown gobies), starfish, acro crabs, blennies, and a pair of clownfish. The main concern is that the tang and starfish would not do well in a 75 gallon tank vs a 120. Do you guys think the extra expense is worth it? What would you do?

 

[Mike konesky]

Way bigger footprint. Go with the 120. More to work with, and you will feel better about the fish having enough space. Got room for a 6' 125? If I were a tang I'd sure love the extra 2 feet. Would likely cost about the same as a 120.

 

[blaxsun]

Bigger is definitely better for the type of fish you want, but there's also the added expense - so ultimately the decision is yours.

 

[Amelanchier]

You also might want to think about what you’ll do if you move in a year or two. Will you be able to take your tank with you? Are you setting up a tank that you’ll have to have hand over to your parents/whoever you live with now very soon?