75g vs 90g - Should I go 90g and are my 175MH's enough?

[sdebol]

Hi Everyone:

I'm upgrading my 15 year-old Oceanic 75g to a RR 75g or 90g. I'm really struggling with the decision because I really want the bigger tank though I'm concerned I'm going to really regret the added 4" in height when it comes to reaching in for tank maintenance. Unfortunately, a 120g tank is not an option due to the limitations of the room the tank occupies. Plus, I need to reuse my existing 75g stand to maintain SAF (spouse approval factor)...

My light fixture is a 2x175wMH with Ushio 10K bulbs and 2x96wPC
Coralife actinics. I keep mostly LPS/softies and fish. Are the 175's enough for the deeper 90g tank?

I've read as many "75g vs 90g" posts as I can find and (of course) see opinions both ways regarding the plus/minus of the added height. Other than the added initial and routine expenses and the difficulty reaching the bottom for tank cleaning/rock adjustment, etc., are there any other negatives to the 90g that I'm not considering?

For those of you who switched from 75g to 90g, how many of you are satisfied and how many regret it?

Thanks, as always, for your help!
Steve

 

[Nashlake]

I have a 90 gal reef that I ran for years with only VHO lighting. LPS and soft corals did very well. I had only limited sucess with SPS and clams under just VHO lighting in the deep tank.

I am now running 2 250 W MH and 2 VHO and am able to keep SPS and clams. I had to move several of the LPS as they didnt like the higher lighting levels.

I think you will be fine if to stick with LPS and soft corals.

 

[reefmutts]

How did you like the added height of the tank. I believe its 4" taller... I am considering the same thing but reaching down to the bottom the tank to clean off the glass would be a stretch. Your only gaining height. Thats why I'm considering the 75. Same width and length.

 

[frezel]

75 much better than a 90, less height = more light peneteration
i would tell you to go to 120 but you already said it was not an option, i am in same boat going from 55 to 75, 90 to tall and cumbersome for lights and maintenance for me and 120 is not SAF approved.

 

[mdellyd]

I had to make the same decision on a smaller scale. I had an old 36 inch stand and was deciding between a 38 and 30 which is exactly 4 inches higher, lol. I decided on more water than less height and more water is always a good thing, but more so on my smaller scale so for me the decision was easy and now I have a very nice 38 gallon LPS/Softies tank under 160 watts of T-5 which is plenty of light. I will be moving and upgrading in the future and for me the decision you are debating is an easy one. I would go 90 any day, but I don't intend to keep SPS or at least the focus of the tank will be LPS/Softy and I am 6'3" so reaching into the bottom of the tank is easy. If you are going SPS then I would go 75, but for LPS and softies I would go 90 because the taller tanks just look so much better. Go to a fish store and look at a 75 next to a 90 and your decision will be an easy one. The Black 90's are gorgeous. Plus, the fish would like the extra swimming room. That is another factor to consider. If this tank is corals only then I would lean to the 75 as the extra water and height is not as important and more of a detriment to the light factor, but if you are going to keep fish then extra water and swimming space is always a good thing.

 

[Nashlake]

I agree, it is harder to get good light penatration in a deeper tank. Thats why I went with 250W MH. Could probably have used 400W with clams an SPS but didnt want to deal with the heat. Maintance is easier with the shorter tank. I used the 90 as that is what I had used when I was breeding Discus. Starting over I would probably go with the shorter tank. The only advantage to the larger tank is increased stability of the system with the extra volume, but I dont think there is much differance with the extra 15 gal of water.

You can keep LPS and soft corals with VHO or 175W MH in the deeper tank if that is the direction that you want to go in.