What do you mean "Natural Aquarium?"
The term "Natural Aquarium" can be used to describe different types of planted aquariums, including any planted aquarium. To me a natural aquarium is a low tech planted tank, generally set up to resemble natural types of settings. These tanks are usually a bit less formal than some of the other planted tank styles, and can often include invertebrates as well as fish and plants. I think of a natural aquarium as compared to other aquariums as a country garden is to a more formal one.
What can an aquarium be in?
Well in some ways it can be in any non-toxic container that can hold water, but some things just work better than others. I prefer glass tanks. But I'm old fashioned. Most of my tanks are the plain old rectangular glass fish tanks. There are a lot of fancy new tanks with bowed fronts and different shapes. Most tanks are pretty well suited to do the job. Extra tall tanks should usually be avoided but they can be used sometimes if the extra height is taken into consideration.
A lot of people use alternative items. Once you're hooked everything starts looking like a fish tank. Sweater boxes, plastic tubs, horse troughs are all some of the containers used for fish. In the house it's usually more desirable to be able to see through the container so glass and acrylics are usually used.
A small container of only a couple gallons can be used but larger tanks are often easier and offer more choice of occupants. A lot of hobbyists have a few large tanks and several smaller ones.
Where should an aquarium be set up?
You can put an aquarium almost anywhere with reason. Fish are pets that generally don't offend anyone. There are a few practical things to consider when deciding where to put your aquarium.
You will need to decide how much natural sunlight if any you want in your aquarium. Natural sunlight can be used with knowledge. Just remember that natural sunlight is much less controllable than man made lighting. It will probably come in through an angle from a window, and that will affect your plants growth. It can also get too hot. I've found that filtered sunlight works better, but we get a lot of sun down here in Arizona, so you will have to experiment with your own situation if you want to use it on your tanks.
The strength of the aquarium stand and the floor it's sitting on have to be considered also. Aquariums are very heavy when they're filled with water. Also be sure and consider the traffic of the place you want to put your aquarium. You don't want people or hard objects running into it. Also make sure your aquarium isn't in a place where it will get hot or cold drafts. And consider that you will have to transport water to and from your aquarium.
What about filters?
I don't use mechanical filters. People ask me about them all the time and I don't know what to tell them. My plants are my filters. Occasionally I may use a little air stone in a tank. I have several under gravel filters that I don't use. I have a sponge filter and a small stack of box filters, none of which I'm using. I had an over the side filter on one of my tanks. It's a brackish tank and was giving me a lot of grief. It was working but when I was on vacation the water dried out and the filter no longer works. Right now I don't have any pumps that work either. I just really don't use them much.
The thing is what you're really doing with most filters is trying to encourage the right bacteria and microscopic creatures to live on your filters to clean your water. Those same creatures also are happy living on your plants. Your plants also use some of the other chemicals that can build up in your aquarium. As for mechanical filtration I pull out dead leaves do somewhat regular water changes.
So for the most part I really don't use filters, I can't really recommend them since I don't use them. I started phasing out the filters on my tanks in the early 80's. So I really don't know anything at all about new filters. If you want to use them you should, I just can't really personally help you with them.
What sort of heaters should be used?
I don't use heaters either. Now if you live in a cold place and keep your house like an ice box, which I know most people actually prefer, then you should probably heat your aquarium. I don't use heaters. I live in Arizona, we try to make things cooler here, not heat them up, and I actually like it pretty warm so my house stays in the upper 70's and lower 80's, and my fish room is usually a bit warmer. So I don't use any heaters. I imagine for a fish room it would be rather impractical anyway and no matter where you lived you'd want to heat the room not the tanks. However in you living room that's an entirely different matter and for many tropical fish a heater may be advisable.
The last time I used heaters was when I lived in Montana and that was more than 15 years ago. Back then it was pretty easy. I see they have nice submersible ones that are more affordable now. If you need a heater you'll have to just look around and see what seems best for you and your aquarium.
What kinds of lights are acceptable?
For practical reasons, many people choose to use light fixtures instead of natural sunlight. There are several options, but I use florescent lights almost exclusively. I can't really tell you about other types because I just don't use them. Florescent is easy and works. I've played a bit with the compact florescents and I like what I've seen so far. I find that standard aquarium lights, shop lights and under cabinet lights all work pretty well.
I use shop lights the most. I used to get the cheapest ones, but I've had terrible problems with them not lasting. Now I'm replacing them with the next grade up, they have a chain pull and a bit longer plug cord. I do have some concerns with the safety. I wouldn't want to use the shop lights if you have bubblers or splashing water up into your light fixture. I intend to put new extension cords with a GFIC built in. After working on the Simple Guide to Planted Aquariums with Terry I was convinced that I should get them. Getting electrocuted while working on your fish tank seems like a stupid and preventable way to go.
There are a lot of rules about what type of light works best and how much wattage you should use, but I find in the real world it's not always that easy. If you use the standard one florescent light strip that comes with most fish tanks you can grow some plants but the choice is much more limited. If you stick 2 of those on there, you'll be able to grow a lot more plants. If you use specialty lights or larger ones, you can generally grow more types of plants up to a point. But it is possible to have too much light for your tank. Each set up has to be considered individually.
As to the types of bulbs I use, I kind of play around a bit. I do like the made for aquarium plant bulbs but they're usually much more expensive than some of the other bulbs. If you use the 4 foot shop lights you can get less expensive bulbs. I like the daylight bulbs. I think they also call them cool white. These are the bulbs that look almost blue white. I think they change the names of the bulbs every few years just to throw us off and make us think they've changed them in some special way. I also sometimes like to pair them with the kitchen/bath lights. These have a new name now too I think. These bulbs are pinkish and seem to help encourage plants that grow reddish colors, though this is just a general observation and may not be true.
What sort of substrate should be used?
I know a lot of people like to add a lot of things to their gravel. I'm pretty much a traditionalist here and just use plain old aquarium gravel. I prefer dark substrates. I generally like pea size gravel but play around with other sizes too. I have used sand. I don't really like it as much as gravel. The tank mulm sits on top of it, it flies up when I do water changes, and I just don't really see an improvement in the plants.
What kind of fertilizers or additives should be used?
Some people like to put things under their gravel. All sorts of fertilizers are used, laterite is popular, and there are several additives and special gravels available. A lot of people like to add fertilizers to their tanks in the form of different drops or spooned in. I've played with some of these at times I haven't noticed anything wonderful happening. Some of them have been kind of nasty. I just don't really use them. Fish poop seems to work just fine in my tanks. If you want to explore them I would say great, maybe your water is different. You should do what you feel comfortable with.
What about CO2
I don't use CO2. I've seen some really pretty tanks that do. I think you can get very nice results with it if you want to use it. It's just a lot of extra work, especially with the number of tanks I have, and it can result in disastrous accidents for the fish and other animals. I just don't use it and can't really tell you anything about systems you should use because I've never used one.
What kind of plants will grow in a Natural Aquarium?
Many plants will grow in a Natural Aquarium, the possibilities are almost limitless. The types of plants you grow can be affected by your water, lighting and many other factors. If you want to know more on plants please look at our Plants section.
What kind of fish can go in a Natural Aquarium?
There are a many fish that will do great in a Natural Aquarium. Generally smaller fish are more suited to a planted tank in general. Some fish and other animals that are destructive vegetarians are obviously going to be a problem in any planted aquarium. Take some care in choosing fish that will like the water, foods and environment you intend to provide them with. Make sure intended tank mates are compatable. Many books and web sites have information on specific species of fish.
What sort of invertebrates can go in there?
The most commonly noticed invertebrate in the aquarium is usually the snail. There are quite a few available. Some will more than likely come see you whether you want them to or not. Shrimp and other invertebrates are becoming more available in recent years. Some of these are very beneficial to almost any type of planted aquarium. There's more information in the Invertebrate section.