The marine mollusk Aplysia californica is an important model organism for neuroscience research. In laboratory aquaria, animal waste may accumulate an Show moreThe marine mollusk Aplysia californica is an important model organism for neuroscience research. In laboratory aquaria, animal waste may accumulate and harm animals unless water is replaced frequently. To keep animals healthy for longer, we have designed a marine environment that replicates the natural nitrogen cycle. Our animals’ holding tanks have two compartments: a main compartment for animals and a refugium for macroalgae. We are studying whether ammonia and nitrate derived from animal waste cause illness in Aplysia, and whether macroalgae can sequester nitrates and reverse illness. We measured increases in nitrate and ammonia in the absence of macroalgae. We also tracked markers of poor health in animals as waste products increased. We hypothesized that macroalgae sequesters nitrates, and the accumulation of nitrate can lead to health problems of Aplysia. Show less
