Related FAQs: Bladderwort Plants for the Aquarium Garden, Related Articles: Live Plants for Aquariums, /The Aquarium Gardener Series The Amazing Bladderworts, Genus Utricularia
by Bob Fenner

Often overlooked as "not being very pretty", or worse, not sold in the hobby "because it grows too fast, and (therefore) nobody will pay for it (!)", the bladderwort genus Utricularia ("You-trick-you-lair-ee-ah") are hard to find in the west. This is a shame; as perennial plants the aquatic forms make undemanding floating or mildly rooted aquarium greenery.

Two stipulations must be made in regards to the use of Utricularia. The first is the all-to-common disclaimer that there are tropical and cold water species, and of course you need to sort out which to put where. The second is that these plants are carnivorous! Don't panic; they won't eat the family dog. Their common namesake refers to tiny bladder-like organs (utricles), hollow spheres equipped with pressure sense and a trap-door, capable of detecting, sucking in and trapping small aquatic life like infusoria and Daphnia, or very small fishes; slowly dissolving their protein to take up as plant food.

But don't lose sleep; unless you're purposely reproducing fish in a tropical system, "the thing that ate Cincinnati" will not consume your livestock.

Classification & Species of Use To Aquarists:

The genus Utricularia is the only member of it's family, the Lentibulariaceae, of interest to aquarists. There are some two-hundred fifty species of bladderworts, twenty one in the U.S. alone, the larger of which have utricles of up to 1/4 inch in diameter. These forms cannot be trusted with fish fry.

The individual species of bladderworts are difficult to discern without careful examination of their white or yellow emersed flowers with their snapdragon spur looks. The varieties of aquarium use can appear quite different under varying growing conditions.

Utricularia vulgaris L.

Common bladderwort

Synonyms:

Natural Distribution & Ecology: Europe, North Africa, U.S.. This is a cool water species best kept below 70 F. in acidic to neutral pH water ponds.

Physical Description:Stalks of up to a few feet in length, with green-brown leaves pinnately divided and further sub-divided into hair-like segments bearing tiny bladders.

Utricularia exoleta R. BROWN

Dwarf bladderwort

Synonyms:U. ambigua, U. biflora, U. elegans

Natural Distribution & Ecology:Portugal, tropical Africa, Asia and Australia. A more suitable warm-water aquarium species of the group. In captive use, the bladders of the dwarf Utricularia are of no concern as "baby-catchers"; indeed, this plant is useful for providing young livebearers and egglayers with hiding space.

Physical Description: Thin, long stalks with small (1/2 " maximum) spiky leaves, alternately arrayed.

About "other" Utricularia species; these are traded through advanced hobbyist and cultivation circles, and variously described (note, not taxonomically classified) by this or that characteristics group or instantaneous "scientific name" du jour. To not dismiss these offerings out of hand; but such material should be quarantined for a few weeks and tested for whether it is tropical or temperate.

Pests, Parasites, Disease:

The biggest gripe of and with bladderworts is "hair" algae, usually a matter of a lack of sufficient iron with an abundance of other mineral nutrients. Either make all fertilizer rate limiting, or provide enough iron. Heavily infested Utricularia should be cut out and tossed to salvage the remainder.

Cultivation Notes:

Bladderworts physically break up rather easily; so either place them in still waters or grant yours a calm corner. Though some species will root and are found as such in the wild, most aquarists allow theirs to float freely.

Substrate/Soil:All Utricularias appreciate organic material and clay in the gravel of their system. Some mud and peat should be mixed in the substrate or water change media filtered through the same in anticipation of use. Beware of hard, alkaline, lime-bearing rock gravels.

Light/Lighting (intensity, spectrum, duration):Enjoys bright light; 2-4 watts full-spectrum per gallon.

pH, KH, Other Chemical:Most aquarium species do best in softer (to 30 KH), acidic to neutral pH water.

Temperature Range:Marshy, cold to cool water types from outside thermal ranges to upper sixties F.; tropicals to mid eighties F.

Species Kept With:Colder water species with Isoetes, Eleocharis and cooler water varieties of Vallisneria and Myriophyllum. Tropical species excel with competitive light hogs like Vallisneria, Sagittaria and Elodea.

Trimming:You can simply pull and break or cut off excess material. Be careful to not carelessly introduce bladderworts (even just pieces) to systems you don't want it in. It gets away easily and is difficult to eradicate.

Propagation:

Usually done asexually with all species by cutting or breaking a portion of living material and transplanting to new quarters. Sexual reproduction by flowers in aquariums is rare.

Acquisition/Import Notes:

Ideally, you may be able to acquire some Utricularia from a local source; already adapted to your water conditions, at least being afforded the opportunity of asking your supplier how they're growing it. Alternatively, shipped specimens should be "babied" initially by matching water quality from their origin; and if necessary, acclimating it to harder water, warmer or cooler habitat.

Close

The bladderworts have limited use and popularity in the west. In European aquarium circles, on the other hand, a handful of species enjoy wide deserved popularity. If you can get your hands on one of the more tropical species, please "share the wealth" by trading or donating cuttings with other hobbyists.

Utriculariaare good, fast-growing plants, that can provide year-round greenery and algae control (through nutrient and light use); and spawning medium and refuge for your fishes, if you have the right species.

Bibliography/Further Reading:

Anon. 1974. Bladderwort-the fish-eating plant. Aquarium Digest International 2(3):1974.

Baensch, Hans A. & Rudiger Riehl. 1993. Aquarium Atlas, v. 2. BAENSCH, Germany. 1212 pp.

Brunner, Gerhard. 1973. Aquarium Plants. T.F.H. Publications, NJ. 159 pp.

Riehl, Rudiger & Hans A. Baensch. 1987. Aquarium Atlas, v. 1. MERGUS, Germany. 992 pp.

Riehl, Rudiger & Hans A. Baensch, 1996. Aquarium Atlas, v. 3. MERGUS, Germany. 1103 pp.

Roe, Colin D. 1967. A Manual of Aquarium Plants. Shirley Aquatics, England. 111 pp.

Stemmermann, Lani. 1981. A Guide to Pacific Wetland Plants. U.S. Army Corps of Engineers, Honolulu. 118 pp.

Stodola, Jiri. 1967. Encyclopedia of Water Plants. T.F.H. Publications, NJ. 368 pp.

Wischnath, L. Undated. The greater bladderwort, Utricularia vulgaris. ADI #35.

Wischnath, L. Undated. A new species of bladderwort for the aquarium. ADI Aquatic Plants. ADI #36, pp. 24,25.

Graphics Notes:

1) U. exoleta growing outdoors in a pond at the Thiele's Naranja farm in Homestead, Fla.