Tank Size Selection for first Reef Set-up


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Hi all. Awesome forum. I am completely new to SW and reef tanks, well, not to mention, keeping aquariums in general. I have been doing the best that I can to search and learn here and on other forums. I also just bought "The Conscientious Marine Aquarist" and have started reading that.

Here's my situation:

My wife and I want to get a large size aquarium and start a reef tank. Today, I re-arranged the living room and was able to dedicate about 3/4 of one wall to this aquarium. Prior to this, I had a couple not so ideal locations, that limited my tank size, so today's breakthrough threw all my plans out the window.

I am contemplating getting a 75g or a 120g tank.

I would like to know what you all would do if in my situation and why.

Also, I am open to other tank sizes and the reasons why I should look at them.

I would like to do it right the first time and be content for years, then purchase small, then upgrade in a year, then upgrade again. But, I also don't want a 60000g just so I never have to upgrade.

I definitely appreciate everyone's help and advice.

http://www.atlantareefclub.org/forums/showthread.php?t=1046">Aside from having a 120 for sale at this time...</a> I still think that the 120 is the better choice BECAUSE...
1. the obvious greater total volume.
2. Having the 2ft front to back gives you much more options for aquascaping. (thats the big one for me)
3. more space = more LR = more filtration = more livestock = happy wife (how can you go wrong there?)

I'll let the others add their opinions...
I agree with Tony 100% - for pretty much all the reasons he lists. It's got a nice depth to it, and it's bigger than a 75g. The front-back depth will really come into play when you start to aquascape, and make it look much better. You'll most likely outgrow a 75. A 120-180 is about perfect.
I third the motion. cased closed! seriously, though, it is a very nice shape that leaves you plenty of options. Also, the greater water volume can be more forgiving for the novist, given its greater potential for stability. My advice would be to TAKE YOUR TIME (it will start to sound like a cliche here but there is a reason for it!), and have somebody from the club who is knowlegeable help you set it up. tcsia does have a great set up for sale and I'm sure would be willing to impart his knowledge to you as part of the deal.

Get a 24" front to back tank and make it as long as you can fit (4 ft = 120 or 150, 6 ft =180 or 210). I started with a 90 (18" front to back, 4 ft wide) and it was impossible to aquascape unless you like the wall-o-rock look.

For my next system, I chose the 210 24" front to back, 6 feet long and 29" deep top to bottom over the 180 (24" top to bottom). I think the 5" extra height looks better proportioned plus the extra depth make for more lighting zones. If you can find a newer used aquarium, I say go for it, otherwise buy new. The extra few bucks you spend on a new tank will be peanuts when you consider all the money you will spend on eqipment and livestock. You need to decide right away wheather you want to run a sump or if you will go sump-less since the aquarium you buy will need overflows built in if you go with a sump.

Before buying anything, READ READ READ, there is tons of information on the Internet on the subject of setting up a reef tank. There are also several great books. Of course, you can always ask us what we think you should do, we love to offer up our opinions :).

Take your time!! Do not expect to setup one of these fragile systems overnight. Prepare yourself for taking it slow. Nothing good in a reef tank happens overnight.

Join ARC and check out our sponsor stores. As an ARC member, you get a 10-20% disount on equipment, livestock and foods at the sponsor stores.

Also check out
a> for another friendly forum for Q and A.
I have had a 15, 55, 90, and 110 and the widest has been 18". I wish my tank was 24" from front to back.

reef1973 wrote: Of course, Tonga is more appealing than the Caribbean rock in my opinion.

...because of size, shape, density, etc - not because of the function they serve. Rock made from concrete and oyster shells (aragocrete) is just as effective as $13/lb rock. Also keep in mind that Tonga rock is not aquacultured, whereas Caribbean rock is.

reef1973 wrote: You will need UV sterilizer and a protein skimmer. The benefits will outweigh the disadvantages.

You will not need</em> a UV sterilizer - the vast majority of tanks get by just fine without them. I don't want to pick on reef1973, but here's a case in point where suggestions will differ with different people. It's up to you to research and decide what is best for you.
I wasn't saying that a UV sterilizer wasn't useful or beneficial. I was simply making the point that it's not needed for a successful reef tank. I use ozone and could argue the same thing.

Basic reef requrements are tank, good lighting, clean water, live rock, and a skimmer. Anything beyond that may be beneficial or just a gadget, but is not a requirement.

I'd be happy to discuss the merits of UV and ozone in another thread, but new reefkeepers should start with the basics and go from there, IMO.
I agree with Mojo here. Some would argure that a skimmer or calcium reactor are not requirements either but I wouldn't setup a reef tank without them! Some would say halides are required, others T5s, others PCs or VHO. In the end, it is up the the reefer to decide what he/she is going to keep in their tank and choose the proper equipment to help that livestock thrive and to meet their levels of required maintainance or ease of use.
Maveri9720 wrote: I am contemplating getting a 75g or a 120g tank.
I agree on the choice everyone else endorses for the 120. Mainly on surface area of the bottom. It opens up more of the tank and gives a much more interesting area to work with. I had a 75 and it seemed cramped.

That said, remember that with the considerable difference in volume (60% increase in volume, to be exact), you have to consider the increased cost of everything from water changes on up to circulation pump requirements, lighting, chiller, rock, power costs, and even the need for increased dosing and/or suitability of calcium methods to that size tank. There are better minds (by far) than I at giving advice on those requirements for a 120, but I do know the last thing you want to do is stretch too far on startup and not be able to afford to upkeep the tank correctly for what you put into it. Enjoy the hoby and go full-out, but plan appropriately. :D
Hi reefers!

Everything everyone says is true, the depth, length and overall look of the 120 is spectacular without monopolizing the room, but definently makes a statement, especially when you consider it as a living piece of furniture . That said, with the amount of water volume for mixing and changing this monster being considerable, I'd like to offer a suggestion to make that necessary chore easier. I purchased at Home Depot (2) 34 gallon Brute plastic trash cans and the locking base on wheels for each. I would have purchased the 44 gallon however, I had (2) 46 gallon bow-fronts so I didn't need that much volume. I use 1 can to mix in and 1 can to siphon old water out. I drip my RO water into the one marked for salt water and when full (measure with buckets how much water you want to replace and mark a line inside the trash can) I run the mag 5 for 24 hours before I mix the salt. This may or may not be necessary but then I Add salt and let it rip until salt is mixed. I feel better doing this for a couple of hours. I use a 1 inch hose and attach to the mag 5 after removing old water and just let the pump do it's thing and replace the water in the tank. I then wheel the old water can out on my deck and with the mag 5 pump the water out of the can into my flower bed. Very easy on a bad back or one that will become bad from schlepping all those buckets. I do a 30 gallon water change r<span style="font-family: 'Times New Roman';">eligiously</span> every week. So far, zero readings and perfect PH & ALK. Then cans were about $25 and the locking bases were $28. A very worthwhile investment to me having had back surgery 3 years ago.
I almost forgot to mention another wonderful helper when working a large tank. I purchased at Home Depot a metal platform ladder that expands the front of my tank with secure locks, light weight and easy to set up. It has steps on both ends that allow you to just step up and walk the length of the front of the tank. It sure beats having to move a step ladder and bucket every foot or so. It raises you up about 2 feet and makes working a tall tank so much easier, especially if you are a shorter person. In my case the top of the tank hits above my eyebrows so reaching into the tank from the floor would be impossible. It was the best $34.99 that I've spent besides the Brute cans on casters which scaled down a water change to about 15 minutes.:thumbs: