i have had my jack in y 100 gallon tank for the last 3 months...i bought him and a firemouth at the same time,the firemouth has doubled in size but the jack dempsy hasnt growen at all???....he dosnt seem to be eating at all his stool has gone clear and white...so i moved hi into a smaller tank 30 gallon,and now all it does is go up and down in the corner..for the last day and a half anyhow, is this just stress? or a i doing somthing wrong?