Can't say I have seen lemon tetras, but I know that Golden tetras are real little stunners, but really your best working out if you have a colour sheme in mind what decore you like and what your current water is like then work from there for suitable fish. It just gets heart breaking when you have your heart set on one type of fish but it's either not availble to you or your water just wont support it without a lot of chemical meddling.