Aquatic life
Water Soldier

The Water Soldier (stratiotes aloides), sometimes called 'Water Aloe', is a member of the family Hydrocharis, so is closely related to the Frog-bit (hydrocharis morsus-ranae) and also to the Canadian water weed, Elodea Canadensis, and to other Elodeas. It is an interesting plant which has numerous tough, sword-shaped (hence the common name) leaves forming a rosette. In a large specimen the leaves can be 2' (60cm) long, but are usually smaller. It may be rooted but is usually free floating. The roots, which can be up to 40 inches (1 metre) long, when free-floating, enable it to balance in an upright position in the water. The leaves are serrated at the edge so sharply that it's advisable to handle it with care!

In winter, the buds sink, coming to the surface in spring. However, the plant often doesn't seem quite sure whether to sink or float, rising and falling at at various times. For instance, after flowering it forms fruits. Presumably these are heavier then water, for at this time the plant sinks.

Since the plant likes hard water, it can get encrusted with lime. If so it will sink! This is, in part at least, the mechanism which causes it to sink in autumn as growth slows. In spring the new growth is lighter than water, so the plant rises.

It can be quite difficult to grow. In fact Gunther Sterba in 'Aquarium Care' says that it's only possible to grow it in outdoor tanks.

However my father-in-law has, in Cambridge, a small pond where it grows profusely. The parent I took from a pond in Epping forest, where it had probably been introduced. It is not very common in the wild. We have tried seeding some of Cambridge's ponds without success.

In mid October 2003, I put a winter bud (or turion) into my aquarium (at about 26°C) and it has duly started to grow, as the picture shows.

The Water Soldier likes hard water (it's a calcophile) and Cambridge has hard water. My aquarium is partially rain water, so softer than the local water - which may explain the colour of my specimen in the photo. Normally they are a lot darker green. This is a young one, grown from a turion I placed in the tank about 6 weeks before taking the picture. It's about 20cm in diameter.

24 Dec 2001

The soldier has continued to grow and is doing very nicely: it's now some 10 weeks after adding the bud. The soldier is some 40cm in diameter and has two runners with smaller plants on them.

25 January 2003

The single parent, although the largest in the tank, is now one of a bunch of five: the tank is only 4 feet long and is getting distinctly overgrown. However the water soldiers are flourishing. Imminent removal of some of them is necessary!

Many decorative aquarium plants that are sold commercially do not last this long and have to be replaced, so I would say that the water soldier is distinctly a successful aquarium plant! It also has the big advantage that it shows very little tendency to algae to grow on it! However - it does get big so is certainly not suitable for small aquariums!

StratiotesT turions/jpeg
Picture on right shows two Water soldier turions and a number of Frog-bit turions.

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Last modified: Fri, 24 Nov 2017 12:10:01 GMT
Page first published 27th November 2002.
Page written and © by Richard Torrens