I am no woodworking expert but did my fair share of woodworking projects in my life (i love wood) - i'd try to match the trim to the colour of the 4x4s - and then give the whole stand a nice clear coat (satin, gloss etc whatever you like most). After all its around an aquarium - water splashes, possibly higher humidity etc. The coat will protect it. But again ... thats just me - others prefer to keep the wood surface.