I have been to Peru several times collecting Apistoes. My advise would be to find a guide who can speak the dialect used in the area around Iquitos. Although going in a river boat west of Iquitos will get you near collecting sites for A. eunotus, nijsseni, agassizi, cacatoides, and Apistogammoides, there is good collecting around Iquitos itself. You will need a pole net that is very sturdy. The ones that you can get in sporting good stores are inadequate. Also if you can get a hold of one of the square German hand nets, these are terrific. You will need alot of shallow plastic basins to keep your fish in. Because of the heat, the fish are very sensitive and will not survive in deep basins. Alot of these fish come from rather cool water compared to the ambient temp. Swimsuits and t-shirts are adequate to collect in. You will need foot ware. I use "reef walkers" but the thick mud tends to suck these off. They worked very well in the Morichales of Venezuela. Don't try high topped boots. Bring bug repellent, this will also remove leeches if you collect in Apistogrammoides territory. Water testing meters are nice if interested in keeping collection records. Thermometer and GPS also good. Bring extra money. I have always had to bribe the soldiers at the airport to let me get the fish out of the country. Also, do not plan to stay very long. One week is about right. Fish deaths rapidly increase the longer the stay. Tom