I'm getting irritated at my Buenos Aires Tetras. They will snack on many plants in their tank. Vals, Dwarf Sags and Christmas Moss have been eaten into oblivion. Am I not feeding them enough or are they just going to snack on any softer plants no matter what I do? I'd like to have more diversity of plants in the tank, but I feel that most of the ones I'd like to add would just be lunch. Any suggestions?