First off I'm a newbie to SI and to the BBC board. I just bought my997 from stillbear in the for sale forum. Thanks for the great deal Gary! My question is last summer I built some large pvc structures. They are in 20ft of water but I can't see them on SI. Reg. sonar is no problem. I'm wondering if I'm not using the right freq. Or if there is something else I should be doing. Also I'm wondering how to post a pic here on the board. Sorry I told you I'm new at this. Thanks in advance. Joey