You have your tank and you have it where you want it. Now it’s time to put the rock, water, and sand in it. This is the easiest part of everything. You don’t have to get all your rock at once. And unless you have a ton of money to put into your saltwater tank, you won’t either. Live rock is the most expensive thing, next to your fish itself.
Live rock is basically what it sounds like. A rock with life on it. There are small creatures on live rock that help to make your tank safe for fish and reef creatures. It is one of the most essential components of a tank. If you have a fish die in a newer tank and go to the store for a refund or exchange, the clerk will ask what you have in your tank to cycle it. They are looking for live rock more than anything else that you have done. Cycling is the term used to get your tank ready with the proper bacteria and algae in your tank for most fish.
Live rock is expensive. Most places sell it for about $6.00 per pound and a lot of round rock is about 3-6 pounds each. Some places you go wil have other kinds of rock, like shelf rock. Shelf rock is great for stacking and caves for your fish. It is what I prefer but I have a reef tank with fish that like to hide in caves. You can also mix the two kinds. Shelf rock can be a little more expensive (like about $7.00 per pound) but due to shape can be about 1-5 pounds instead. It is based on preference and how you want to set up your tank. To start with you should get about 2 pieces of live rock in your tank. Even with a big tank, you can add later. More rock is less water in your tank because of the displacement. It’s best to add live rock when you do water changes so that you already have the water out of your tank when you add the new rock.
Sand is important too. It comes in different kinds here as well. Sand with bacteria in it (which will help cut your cycling time down), dry sand, shells, and other kinds of sand. Whatever you do, don’t go cheap here either. My first tank we used some bacteria filled sand and the rest crushed shells. This was a mistake because I ended up with ich (a disease) and it wouldn’t go away because even though the fish would get well, the ich was living in the shell pieces and kept coming back. We had to dump the tank completely, get rid of all the sand and buy all new sand to replace it. It took all day and was something I wouldn’t want to repeat or let anyone else I know make the same mistake. The sand with the bacteria is more expensive (because it is from different parts of the ocean) but worth it to have that extra bacteria to help your tank mature (cycle) faster. By the way this sand is usually called live sand becuase of the bacteria in it. The live sand also comes in different kinds from different parts of the ocean. It doesn’t matter what kind of fish you are going to have to pick your live sand, it’s a preference for what your tank looks like.
Your sand bed will need to be about 2-3 inch bed. The 3 inch is better. More room for your sand sifting creatures to move around. To achieve this you will have to buy anywhere from 2-6 bags depending on your tank size. Of course if you have a Nano you probably wouldn’t buy even one bag because it would be to much.
Add your sand before you put in any water. You can also mix dry sand with the live sand to save money. Just put the dry sand on the bottom and make sure to wash the dry first to clean it. Otherwise you’ll have a cloudly tank until the “dirt” settles.
Now after you have the sand in, you add water. If you don’t buy Reverse Osmosis saltwater from a store, you will have to buy salt and mix your own. Reverse Osmosis can be better because it’s had all the bad metals found in tapwater removed and is a consistant PH. It looks more expensive at first, but the time you save trying to measure your salt and mix it yourself can be worth the money. And actually I have found it’s really not anymore expensive than having to buy salt and try to get the mix just right in my tank. But if you want to mix your own, it’s not hard. Salt comes in different size bags. Each bag will say how many gallons of saltwater it will make. So the first time you set up a tank can be expensive to buy the salt (the RO water would be too). You mix your water and salt together BEFORE adding it to the tank. If you have a big tank, it will take some time to mix and fill your tank. The directions for the ratio are on the container and are not all the same. I recommend that you fill 3/4 full and check your salt level and then add water/saltmix accordingly. If you get too low of a salt level you will have to dump water and readd. This takes even more time and is a pain that is easily avoided.
To check your Ph and salt content, buy a hydrometer. It shows the level for both for an ideal tank, no matter what kind of fish you want. Although some creatures like higher or lower contents and can be adjusted later if they don’t like the basic ideal conditions.
Also make sure you add your live rock about 1/2 through adding water. That way you don’t have to take water out for the displacement the rock makes. Live rock should be kept wet until adding to your tank, so I don’t recommend taking it out of the bag the store put it in for you until you are ready to add it to your tank.
And then you have a tank with water, sand, and rock in it. Next is your filter system.