This and other articles will be part of a series of guides for people new to saltwater aquariums. Subscribe to this sub forum to check out the whole series. Step One - Choosing an Aquarium that is right for you Space Decide where your aquarium will go. Figure out a spot in your place where you want the aquarium to go seems relatively straightforward, but here are some things you will wish you knew a year from now: Expect salt creep. Salt creep is when saltwater spray, usually contained in a very fine mist, lands on areas outside of the aquarium and then evaporates. When the water evaporates the salt will remain, building up on surfaces. Lids help cut down on salt creep, but it will still manage to accumulate on uncovered portions of the tank, and on nearby surfaces such as walls. Leaving yourself enough room to wipe down the wall and sides of the aquarium with a damp cloth is something you will really want to have, so plan for it now. Water changes will require you to move 10-20% of your aquarium's water volume from a source to your aquarium. Plan for water changes now, to make sure you do not have to carry water all over your house which increases the risk of making a mess and/or hurting your back. Subscribe to this forum to read how to clean a tank like a pro and keep messes and work down in a future article. Make sure the outlet you plan to use can handle your system. With efficient LED lights that don't require chillers to be used anymore this is becoming less of an issue than it was previously. If you live in a cold environment though, heaters can put a lot of strain on your outlet. Make sure you have enough capacity for the job. If you are unsure of how to do this, you may want to consult an electrician or handyman. Consider installing a GFCI outlet, especially if you have children. GCFI outlets are the kind of outlets that you find in bathrooms above the sink. When wet they trip, stopping electric flow to the outlet. They will also trip when pumps, heaters, or other electronic equipment has a current leak. For a more detailed explanation of the safety features of this outlet, see this link. Outlets should not be directly behind the aquarium, they should be offset from the aquarium and out of the way of "the splash zone". Indirect sunlight from a window will grow nuisance algae, try to locate the aquarium as far from a window as possible. Southern facing windows will bring in more light than windows that face north. If you are putting the aquarium on a carpeted floor, consider placing a runner or throw rug underneath it that can handle high traffic and the occasional spill. Moving an aquarium is a big chore, you will want the flooring to last as long as the aquarium or longer. If you plan to change the floor soon, you may want to do it before putting the aquarium in place. If you have wood or tile floors, a padded rubber mat at the base of the aquarium stand will help distribute weight and protect the floor from spills. These are often sold for commercial applications as "anti-fatigue mats". Make sure the floor is level, or shim the aquarium until it is, before adding water. If you have never shimmed something before, this video has a good explanation. Make sure your floor can handle the weight. If it is going on a ground floor above the foundation, you should be OK. If there are supports holding up the floor, make sure they can handle the weight. A rule of thumb for the total weight of an aquarium is 20 pounds per gallon. This "rule" takes into account the weight of the water, the average aquarium and stand, sand, mechanical objects, rock and some room for margin. Make sure the floor can hold it, and when in doubt ask an engineer or whoever is licensed to do that work in your state. Most importantly, make sure you have a comfortable view of the aquarium. If you have to tilt your neck or turn to see it, you will lose out on a lot of good viewing or end up with a sore neck. Size Generally speaking, the shallower and the bigger the tank the easier it is to maintain. Nano-Tanks are aquariums under 40 gallons, and are considered relatively difficult to keep. Support groups have been formed online to help those people who have taken on the challenge. Why shallower? There are many reasons to get a "long tank" vs a "tall" tank. Fish swim horizontally for the most part, rather than vertically, with the exception of seahorses and a few other fish. If you are considering a reef tank, the deeper the tank the more light intensity you will need to penetrate to the bottom. The additional light source might cause too much heat, necessitating a chiller. You can also fit more corals or other photosynthetic life in a wide and/or long tank because there will be more surface area that is exposed to light. The drawback of a tank that is wide and/or long is that they will have more evaporation vs tall tanks per gallon. Why Bigger? If something goes wrong in the tank, the water conditions will change. In a larger tank these conditions will be diluted over more gallons rather than less, and the impact to the tank's inhabitants will not be as severe. The maintenance of a "nano tank " can be difficult because there is little room for error on the part of the aquarist. At some point a huge tank can become an overwhelming task as well because areas within the aquarium can be hard to access by hand, and the volume of water needed for changes can become overwhelming. A "40 gallon breeder" or bigger should give a beginner enough room to make a few mistakes. Features Some things about one aquarium can make them more valuable than others. Here are some things that I think really matter when determining the value of an aquarium: Drilled for a sump - Any tank that has an overflow drilled already into it is worth at least another $100 more in value than a tank without that feature, unless drilling holes in glass is your other side hobby. Sumps are tanks that hold water in a system that the aquarium is connected to, and are usually contain filtration equipment, media, or refugia. More will be discussed in our filtration section, for now just know that a second attached aquarium helps add water volume, keeps your tank stable, serves as a place to hide filtration devices and generally makes your system much easier to maintain. Acrylic vs Glass - Acrylic is lighter and easier to move than glass, and it is also easy to repair. Glass aquariums can rarely be repaired. Acrylic tanks often boast greater clarity than glass aquariums, but they also scratch easier. Many cleaning products and scrubbers that are safe on glass will scratch acrylic. It is up to you to decide which features are more important to you. Glass or Acrylic thickness - The thicker the glass or the acrylic on an aquarium, the stronger it will be. Today aquariums are often made with the bare minimum required to handle the weight capacity they are designed for. Some used tanks come from a time where manufacturers used far more than what was required to build truly strong and reliable aquariums. If you come across one of these that have managed to stay scratch free, you may want to snatch it up. All in One Systems - These are aquariums manufactured and sold as a set to take some of the work out of building your own system. They usually come with lights, a stand, filtration mechanisms, and other required parts. They can offer a good value over a customized system. Aftermarket Modifications - Many popular models of All in One (AIO) tanks such as the BioCube series of aquariums have after market improvement parts that can add a great deal of functionality to these systems. Companies like inTank (unaffiliated) specialize in these parts, and being able to match up parts after purchase may be something of value to you to consider. High Quality Glass or Acrylic - Mass market aquariums usually have standard clarity, but there are higher clarity glass and acrylic aquariums available from custom manufacturers and companies that sell to the higher end retail market. You should be aware of this, and make the decision on which to purchase with this in mind. Two tanks of similar size and shape may differ in value a great deal if one is made of thick high clarity glass and is drilled and prepped for a sump, and the other is standard clarity and thickness glass that you will have to drill, or use without a sump. These considerations are often more important than whether a tank is new or used, the topic for our next article.