Hey! I would recommend a few things:

1) set up at least two in the same site kind of back to back or side to side if you have that many. Directionality can influence the number of calls you get and it's just good to know your error rate. 

2) Experiment with breaks and recording duration. You wont collect anything if the write time is not long enough to record to your SD card and you'll get empty files. 

3) Clean your device every time you take it out or see visible biofouling. Also, add silicon grease every time to your O-ring. Take it out with an O-ring pick and clean the plastic seal, looking for any type of sand/mud/debris. We've had a few flooding incidences, but this is probably because we open them all the time.  

4) lower the frequency rate the more data you can collect, so keep it as low as your frequency of interest without clipping your calls. Fish are lower than pretty much everything (2kHz-3kHz). 

I hope this helps! 

Oh wow, thank you so much!!!

I will keep that four advices in mind!