yes anubias is a very slow growing, low light plant and it can be attached to bog wood ( best) or a rock and can also be grown on regular gravel but its main horizontal rhizome should not be burried this decays the plant quickly. if you intend to have a high upgraded light for any reason ( other plants or visibility ) give it a shade else its leaves will be mushroomed with algae. good luck.Can you grow Anubias congensis in regular gravel? And without adding ferts to the water column just adding root tabs?