Today I was at a pet store and they had a pair of varadero and a pair of lamasi together in a 20H. I was trying to tell them maybe they should split them up. They guy said recently they had a pair of vents in with the same pair of varadero in the same tank for 10 months with no problems before the vents were sold. He said once the vents were sold he just added the pair of lamasi & even said they have bred but not much. I thought 4 thumbnails in a 20H was too small. I know mixing is frowned upon but has anyone else ever heard of or mixed thumbnails themselves? Also the viv is so heavily planted to the point I would consider it over planted.