Thoughts on Paludarium Design

by John Tullock

Are you the type of person that appreciates a real challenge every now and then? If so, I suggest you look into designing and building a paludarium. According to the Aquatic Gardeners Association, a paludarium is an “aquarium with above and below water aquascaping.” This is not to be construed, as is explained on the AGA web site, as a “terrarium with water in the bottom.” In other words, as much attention should be paid to designing and planting the underwater portion as is given to creating the terrestrial portion of the display.

Having been an aquarium enthusiast for decades, I have attempted a paludarium on a few occasions, and have never been really happy with the results. In thinking about the reasons for this, one of the biggest problems is the difficulty of building a display in a smaller tank. What is required is a tank approximately twice as tall as the desired final aquatic portion, or taller. Most aquarium hobbyists would consider a tank much less than 12 inches deep to be pretty confining, so a paludarium needs to be about 24 inches tall (or taller) in order to accommodate both water- and air-dwelling plants.

The added height means lighting above the paludarium must be intense, in order to suffice both for the terrestrial plants and those living under the water. I recommend investigating the PAR values reported for various lighting systems, as well as taking into account the needs of the plants you are considering, before selecting lighting equipment.

The aquatic portion of the paludarium will require filtration and, possibly, carbon dioxide supplementation, just as if it were a free-standing aquarium holding the same quantity of water. Substrate selection and hardscape should complement the planned terrestrial portion of the display.

Which brings us to the most important consideration of all: make a plan! More than any other aquarium project, a paludarium will benefit from preparing a detailed plan, preferably to scale. Make your mistakes on paper before you make them during construction.

A paludarium can involve considerable expense and effort. Save both with a carefully laid out plan.