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Reported here is a large oligopyrrole macrocycle, a calix[10]phyrin bearing two diformyl substituents. The combination of conjugation provided by two pentapyrrolic subunits and flexibility resulting from the presence of sp3 hybridized meso bridges allows the system to adopt a double tailed, scorpiand-like structure with two near-symmetric binding pockets. In methanol solution, this macrocycle was found to interact with a number of test acids, including sulfuric acid, trifluoroacetic acid, phosphoric acid, hydrochloric acid, and fluoroboric acid, via a combination of protonation and counter anion binding. Species specific behavior was seen, allowing for the colorimetric-based discrimination between the acids. Efforts to model the underlying binding equilibria led to the conclusion that upon treatment with excess H2SO4, up to four protons and two counteranions are bound, whereas in the case of HCl the dominant species is a monoanionic complex. The responses of several other acids were rationalized in terms of these limiting scenarios.