Fish options with a 4' tank vs a 3' tank

boilermaker1

New member
The great debate is on. I'm trying to keep the floor of my new apartment whole (I'm told its 1' thick concrete) so I'm sitting here pondering 75G or 65G.
I have a 29 right now, its overgrown and getting too small, but moving always provides a chance for upgrades.
I'm leaning towards the 75, but its got its pluses and minuses.
The tanks are about 17 bucks difference so I'm not sweating that, and I'll be DIYing the stand so an extra few feet of wood isn't a big issue either. The kick in the pants is the new light, but I don't know if I would have been overly happy with a 2x96PC over a 65G anyways, so I may have bought a new one anyways.
Skimmer would be the same for both, and I assume the AGA overflow is pretty standard, making the return pumps the same size. Couple extra lbs of sand, a few extra rocks, and thats about it. I'm not too worried about dollar issues.
but as far as fish go... how much do my options open up by going to a 4 footer? I was surfing live aquaria, and going more by the size they provide in inches for the fish rather than their recommended gallons... and it seems that there's not a whole lot of reef safe fish between dwarf angels and tangs. Now the tang police doesn't need to tell me not to put one in a 75 , I know better unless I can find a way to keep the rocks really open, but what do people with these mid size tanks do? Pairs and groups of schooling fish? I guess I'd like to get something "large", but I guess I'm realizing its still not that big of a tank. So do my options really change? Or is gonna be wrasses, gobies, clowns and the other 4"ish fish, just in decient number, where going to the 4' tank just buys me some more swimming room?
My tank right now is a bit too rocky. I'd like to open the new one up. I probably have nearly 60 lbs of rock in a 29 after all the rock that hitchhiked in on corals ended up in there.... I wouldn't mind actually starting out with about 75-85 lbs (and adding more corals with presumably more rock stuck to them) and seeing how open that leaves me for more swimming room, then maybe going from there if its not enough.
 
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I bought a 60g 48 x 13 by 24 talland it was fine for a week until i saw that i could get a 75 for the same price 48 x 18 by 20 tall. the wider the better!! fish like to turn around and swim around the tank. I'll never go back to 13inch wide if anything go wider.

also the extra inches of tank height really took alot of impact away from my pc lights --

even a 75 just buys more swimming room honestly -- the next tank i get is a 120 g 60 x 18 for about $240
 
always get the biggest tank you can, why stop at a 75? A 100 gallon isnt longer just wider and will be able to support fish that are far larger than what you can hold in a 75.
 
Not sure what kind of lighting you were planning on, but if you could support the weight of a 90 or 100, the added depth would require a jump to halides or overdriven T5's IMO.

I am in the process of setting up a 75g for LPS. I'm working on my fish list as well. Some fairy wrasses / flasher wrasses, a royal gramma, Cardinals and gobies are on the list at the moment. I will take my 50/50 chance on a dwarf angel of some sort and if you check the Tang post at the top of this forum, there are some suggestions for Tangs at a minimum of 75g. I'm thinking of a Kole Tang for mine.
 
A 75 gallon 48"l x 18"w has 11.52 sq in. per gallon.
A 65 gallon 36"l x 18"w has 9.97 sq in. per gallon.
Assume that the weight of the tank and contents are constant per gallon of volume then the 75 would put less stress on your floor.

Something to think about:
A 120 gallon 48"l x 24"w has 9.6 sq in. per gallon. This is slightly less than the 65. :D
 
No, I'm not worried about the weight of a 75 vs a 65, but I would start worrying about the weight of a 90 or 120 over a 75 (plus a 1/2 full or so 29G for a skimmer sump), which is why I'm looking at mid-size tanks.
Its the 6th floor. It seems quite solid, but I don't necessarily want to push it.... I'm just going off what I was told, but without knowing for sure, I don't know how crazy I need to be getting.
 
doesn't really answer your question, but i'd go with the 75 gal for sure if you're considering fish. it has a 33% increase if floor space over the 65. i've kind of got the same dilema, bought a 58 gal 36"x18"x21'? i'd like to keep the larger fish triggers, groupers, puffers, etc. but the tank is way to small in the long run.
 
I had a tenant who had a 135g on the 15th floor high rise tower apartments.

Concrete floor - no issues. The building was built in 1967, sits on landfill, and had minor cosmetic cracks after the last Loma Prieta earthquake here in San Francisco.

He actually had a 135, 55g, and and 40g tank in his apartment. I say had because he decided to buy a house down the road
 
If the floors are concrete you have nothing to worry about. I had a 58 with a 29 gallon sump on the third floor of a crappy apartment with warped wooden floors. A 100 or 120 with concrete is no problem.
 
<a href=showthread.php?s=&postid=7382279#post7382279 target=_blank>Originally posted</a> by boilermaker1
The weight of it on an apartment floor.
FWIW my 100g is upstairs in our home with wood flooring on the second floor. There's also about 60 more g of water directly underneath the tank in the way of refugium & sump. My tank is 5 feet long. An engineer told me it was fine as long as it is placed along a supporting wall rather than across the room. He said I can extend the tank as much as 10 feet as long as it's along the wall.

One more thing... I wish I had a longer tank. At first my 100g seemed huge --- now it's too small - everybody goes thru this. My advice : get the biggest tank you possibly can.
 
I have a 300 gal on wood floor (I think). Thank goodness it iddn't sink.

I say go larger, which allows you to have more options. Get a 180 so you can keep tangs and angels.
 
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