Most people like green growing plants, and you will find this very human desire expressed in aquariums. Almost every successful and beautiful aquarium has growing plants in it. Contrary to popular belief, it is not necessary to pack your aquarium with dozens of plants. Plant for decorative value, use as few or as many as you desire to make a tasteful arrangement.

Plants like Amazon Swords grow best with a sub-sand filter when the roots are confined. Use small, shallow, cup-like planters, either under the sand or on top of it. These will prevent the roots from spreading and clogging the slots in your filter and also prevent the crown of the plant from being pulled under. If this happens your plants will die.

Aquatic plants fall roughly into three groups. First those bushy ones, which send up branched stems bearing many leaves; these are usually propagated by cuttings, and these are what you are most likely to be offered at the dealers.

Secondly, there are plants which send up a number of long leaves from the same place, or "crown", just above the root. These usually spread by "runners" under the sand, which send up new plants near the old one; the young plants are separated off, and so these will have roots to them when you buy them.

The third kind does not root in the sand at all, but floats at the surface.

It is useful to know something about the different kinds of plants in these categories before you buy them, as they have different uses and requirements. I would warn you against having too many kinds. The conditions in the aquarium are bound to suit some kinds more than others, and these will make rapid progress, eventually crowding out the rest. In a 24-inch tank therefore it is really not practicable to introduce more than three species.

Choosing Plants

When confronted with a huge variety of plants, there is a great temptation to take a piece of everything that appeals to you. If you do this, you will be wasting money needlessly. A dozen different kinds of plant in a tank will compete for food and light, and before long the strongest will have gained the mastery, the others dying off. So exercise self-restraint and limit your choice to three kinds. Two of these plants should be for massing in the background, and one as a center-piece.

Of the three, I would suggest that, for the first aquarium, one should be either Vallisneria or Sagittaria (not both in one tank, as they compete). Another can be one of the bushy plants - Hygrophila is the easiest to grow, but Cabomba Lim-nophila or Ludwigia are more decorative for the tropical tank; if starting a cold-water tank, make sure the plants you choose are hardy enough.

As a center-piece a Cryptocoryne, Echinodorus or an Aponogeton are recommended for warm water, a Hottonia, Muphar or Ranunculus for the cold water.

Healthy plants are plump, crisp and intense in color; refuse those that are limp and pale. Most aquatic plants are rather brittle when out of water and must be handled carefully. Never pick them up by the middle of the stem; the best way is to lift them by the base, so that they hang down from the fingers. Select young, half-grown plants rather than fully-grown ones, and with as many leaves as possible.

Many of the plants which propagate by cuttings will be seen to have fine, hair-like roots sprouting from the nodes from which branches spring; choose these, as they will "take" more quickly.

Plants with crowns must have good roots, and you should examine these to see that they are plump and bushy.

Selecting plants is a great part of setting up your aquarium, so have fun! There are so many to choose from, you will undoubtedly find some to your taste.