Goliathus Question

Hello all,

I have been rearing Goliathus regius larvae for the past 4 or 5 months now, acquiring them as late L1/early L2 larvae. I rear them in a coconut fiber substrate and feed them koi fish pellets that I rehydrate in water for ~10 or so minutes. Initially, they seemed to do fine, rapidly gaining in weight and development (they quickly molted to L2 within a week or two then from L2 to L3 within a month).  The first couple months of L3, they gained about 7-10 grams a week but lately I've noticed it has slowed down quite a bit. I see little weight gain, perhaps 1-3 grams a week at most. I originally thought it was a mite/sanitation problem so I washed them and replaced their substrate every 7 days. However, this has not improved their weight gain. Lately I noticed they clump the fish pellets i give them into big balls of substrate (the amount of pellets I'd find clump also varies but it usually is maybe 1 or 2-3 at a time). I do think they are still eating some of it since they are not rapidly losing weight. But they are not gaining much either (again, perhaps 1-3 grams a week, usually closer to 1 or 2). Has anyone else observed this behavior before in their beetles? 

 
How large of a container do you have them in and how much substrate is in the container? I have changed from coconut to composted sphagnum moss. Their growth does slow down a bit in L3, especially near the end.

 
I keep them in 24 oz food containers. They're flattened trays that are 1.5 times their length and as wide as they are long. I keep them in enough substrate for them to bury themselves fully but it is a little on the shallow side. I don't think they're ready yet to pupate since they haven't started wandering yet. But I suppose they've still got a few more months before they're ready.

 
If you can send a pic of one of the containers it might help. So far everything sounds ok. Substrate should be on the dry side but not totally dry. When I feed them I place the pellets right in front of their mandibles, so they don't have to go looking for the food.

 
Back
Top