you using tap water? as leakage color is brownish, if it was zic coolant it should be green residue. i am not ver familiar with honda engines, the leak int he first could be hose pip erooded on the joint, though unlikely as it seems fine, it could be leaking from the flange where it connects the head or the thermostat housing if its present in that place. it cant be leaking from the actual engine block or i dont think you should be worried about a crack in the head or block as otherwise you would be loosing oil or compression as well.