i have an albino bristlenose. when i first got him; he was a very pretty light mango color. in the past week or so, he seems to be losing his color. he is pale. now in the past two days, he is taking a small bite out of the algae wafers then he leaves. is he about to leave me? any ideas on what's going on with him? he ate every bit of the algae in the tank when i first got him about a month or so ago. no more algae is there & none has grown so could this be the problem also? thanks.