I always get nervous about cyanobateria in freshwater enclosures as a number of species of freshwater cyanobacteria also produce toxins.. and there are reports of amphibian deaths in the literature (see
Reviews of Environmental ... - Google Books) and in relation to fish keeping (See Ecology of the planted aquaria, Echinodorus Press).
I'm not saying you will have a problem, just that I get nervous.
Ed
