Should I upgrade to a 75 or a 90?

[that Reef Guy]

I currently have a 55 Gallon Aquarium.

I wish I would have started out larger with a 75 or a 90 as I would have 6 more inches to aquascape with.

Here are the dimesnions:

55 Gallon 48" x 12" x 21"
75 Gallon 48" x 18" x 21"
90 Gallon 48" x 18" x 24"

All are 4 foot long Tanks.

So I am debating on the 75 and the 90

75 Pros
Cheaper (Not really important)
6 more inches of Gravel Space for Aquacaping
18 inches deep instead of 24 so more Light hits the bottom of the Tank.

75 Cons
Less swimming room for Fish



90 Pros
6 more inches of Gravel Space Aquacaping
15 more Gallons of Water to make the Fish happier

90 Cons
More expensive (Not really important)
3 Inches Deeper (Less Light hits the bottom of the Tank).

I want to go with the 90 Gallon so my Fish have more room but my Biggest Concern is the fact that it is 3 inches deeper than the 75 and less light will hit the bottom of the Tank affecting my Corals (Plate, Acan Lord, Green Wellso, etc).


Is the 3 extra inches in height going to make that much of a difference in terms of Lighting?

What should I get the 75 or the 90?

Has anyone else run into this dilemma on the site?

If so which Tank did you choose and why?

How did your descision turn out?

[Sir Patrick]

What type of fish, coral, and lighting do you plan on having???

This little bit of info will help answer your question.

Normally, I say bigger the better, but there are some variables.

[that Reef Guy]

I have a Marineland T5HO 4 Bulb 214 Watt Fixture on my 55 Gallon.

I might get another (Do you guys think that will be too much light on a 75/90 Gallon). 8 Bulbs

The big thing that I am worried about is the Lightning.

I read in a book that T5 lights can only penetrate into 18 inches of water. While Metal Halides can go down 39 inches.

I do not want to have to get Metal Halides. I currently have problems with them.

I would definitly go with the 90 gallon but it is 3 inches taller so I am worried about the corals I keep on the bottom of the Tank not getting any light and dying on me (Torch, plate, etc).

Thanks in advance for any help on this decision,
Steve

[Sir Patrick]

My tank is just as deep as a 90, and I run a 6 bulb setup, with individual reflectors. * would be great! Run both fixtures with ATI bulbs, and you should be good for most coral, with proper placement.

I keep sps mid to high, and lps (plates and torch) on the bottom without difficulty.

[steve&mari]

We run I think the same tank as sir a 65 36x18x24 with a 6x39w aquaticlife fixture. We have clams on the sandbed that are doing great growing fast n full of color. Also our plate n acans n such are on sand or bottom 8 inches and do great. Sps are mid to high in the tank and are growing have great color and have great polyp extension. Rose mille has better color then it did at preuss under mh and its bout halfway down on rock. We also run all ati bulbs 4 blue plus 1 purple plus and 1 aquablue special. We added 2 453 nm stunners across the front for extra pop you get with leds going to add 2 more across the back sometime aswell. We love the look they give but they aren't much for par jus pop. Our nems are high in tank and very happy they open nice n big and have a cool look under the leds. So with that all being said I think you'd be fine with a 90 if ya do lighting as your talking of. Hope this helps alil n good luck with whichever you choose.
Happy reefin
Big Steve

[rmalone]

I personally like the look of 75g better than 90g. The 90g always seem a little tall relative to length, but that is simply a personal preference. I should add that I really like the look of short, ling tanks. I wouldn't worry about getting enough light to the bottom for lps, I have seen a ton of 90g with even pc's and lps are just fine on the bottom.

[that Reef Guy]

Thanks for all the responses guys. I really appreciate it it.

If I get another Fixture that is the same as my current one (The 4 Bulb Marineland). Will that be Ok or will it be too much Light.

I do not want to have any algae problems.

Some of you said you had 6 Bulbs. Would 8 Bulbs be OK or would it be too much?

[Sir Patrick]

I think you would be fine. If its too much light, you could always put in some lower par actinics.

[dlhirst]

I think the 75G is going to give you the same amount of usable aquascaping space. Now if larger fish that need open space is a big priority, the extra 3" really adds a lot. Like rmalone, I like the not so tall look, but that is totally subjective. The jump from 12" to 18" front to back depth will really add tons of opportunities - and you can create plateaus in your reef rock to raise up those corals needing more PAR (if you decide on the 90).

[Hal3134]

90, no question. 3 inches won't make much difference for light penetration.

Have you looked at any 120g's?