It would be easier for me to tell them apart if they were grown submersed. Crypt #1 looks like C. x willisii---used to be called lucens or nevillii
Crypt #2 might be (I am guessing!) C. walkeri ?
Crypt #3 might be a young C. wendtii
Crypt # 4 cound be either C. pontederiifolia or C. moehlmannii