First of all thank you to everyone contributing on this forum. I have spent countless hours here over the last few weeks soaking up as much information as I can. Santa Claus brought my daughter a 29 gallon tank for xmas. We cycled with tetra safestart and our values are 0 ammonia, 0 nitrites, 5-10 nitrates, ph 7.8, temp 75f, some silk plants and fake rock in the tank. Substrate is mostly pool filter sand with a little fine gravel at the back underneath the filters, plenty of hiding places. We do 30% water changes every sunday with seachem prime and have two filters, one hob and one canister, giving us about 300g/h filtration. Water is crystal clear, all fish seem healthy and playing with each other. Right now we have 5 female platys and 4 male guppies, which we added slowly over the last 2 weeks, all according to the tetra q&a instruction page. They all get along great. To complete our tank we were thinking about maybe neon tetras or some juli cories and another platy. What do you think we should do? Naturally we are also open to other peaceful species. Thank you everyone for your help and advice.