My depth finder keeps loseing the bottom and just flickers the last reading

SOURCE: How do you get the fish to show up on the screen

Are you looking for the little fish symbols?
Press MENU, down arrow to SONAR FEATURES and press ENT. Arrow to FISH SYMBOLS and press ENT. Press EXIT twice. Any significant return in the water will now show up as a fish symbol.

Are you looking for the fish arches?
You won't get any arches unless the boat is moving and of course there are fish passing within the transducers signal. The shallower the water, the less area you are covering and less likely to get a fish return.

There is an OK guide to understanding what you see on the sonar screen at the link below. It if pretty technical but parts of it may help you out.

http://primus.lowrance.com/support/resultDisplay.do?gotoLink=5&docType=1000&contextId=351%3A5.47%2C11918.11930%2C22.47&clusterName=ClusterPublic&lang=english&docset=%2FDocuments%2FSonar&contentId=9de88fa2-0b60-4b44-a470-29ee14767b3e&responseId=135ccbe2cfd4f608%3A1fe88d%3A122773df7e0%3A7c2&groupId=4&answerGroup=1&score=981&page=http%3A%2F%2Fprimus.lowrance.com%2Ficr%2FSonar%2FChart+Tutorial.htm&result=0&excerpt=Chart+Tutorial+Deciphering+Sonar+Charts.&question=chart+tutorial&resultType=5000#Goto5

An X96 owners manual can be downloaded from http://www.lowrance.com/en/Downloads/Manuals/

SOURCE: I need a manual for my lorance x38 HD fish

http://www.retrevo.com/search/v2/jsp/mytrevo/myTrevo.jsp?page=man download a pdf version on this page

SOURCE: Lowrance LCX 28c HD with Navionics HotMaps Premium SD chip. Chip worked fine last fall but when I went to use yesterday the Lowrance would not read the chip.

I had the same problem with my handheld Lowrance Hunt C. After installing the card and locking it in place, I had to slide the card "out" toward the locking mechanism. It barely moves, but worked after that. Whenever I load the card, I now slide it out or wiggle it and it works every time.

SOURCE: transducer loses bottom at any type of speed

Check the transducer for any damage on the front part. Also make sure there isn't any damage on the bottom of the boat that is causing air bubbles to cross the face of the transducer. If it works at slow speeds there is definitely something causing air bubbles.

SOURCE: When at speed i tend to lose sight of the bottom

What you are experiencing sounds like air bubbles crossing the face of the transducer. If you have a transom mount transducer check the face of the transducer. Make sure that it is clean. Also make sure the front of the transducer is a tiny bit lower than the back. The digital readout on the screen will only happen when you have a strong signal of the bottom.