I am in the stages of needing a PH meter and was wondering what the best one for the money is ??? I have been looking at the Hanna but there are two different ones and I am a little confused. They have a model# 98129 and then they have a model# 98130 but they look exactly the same to me. Can someone tell me what the majority of growers are using ???? Can anyone give a suggestion as to a GOOD ph meter to buy ??? Thanks for any and all suggestions.