This is all anecdotal, but I recall hearing it from multiple sources. Some people say that bubbling is affected by lighting, flow, or nothing at all. Others swear it's due to how they feed (I'm now one of those people).
A few years back, when I was first starting out, I remember watching a video on YT from an importer who claimed to be a biologist (no idea if the second part is true or not), but he stated that nems stretch out when they are being fed more physical foods. This allows them to have longer reach and capture more prey. When they are strictly relying on light for nutrients, they bubble up to increase surface area and capture more light.
I had my nems for a year in my main display where they were broadcast fed mysis daily with the rest of the tank. In that entire year, I could never get them to bubble, just the occasional "fat tentacles" where they look more like chubby little fingers than bubbles.
After moving them to their own tank with the clowns, and only feeding tdo pellets to the fish, they have never looked better. Par, spectrum, water quality, and flow are more or less the same. The only difference I can see is that they are no longer eating (the clowns are not feeding them either).
Just thought I'd share my experience.
A few years back, when I was first starting out, I remember watching a video on YT from an importer who claimed to be a biologist (no idea if the second part is true or not), but he stated that nems stretch out when they are being fed more physical foods. This allows them to have longer reach and capture more prey. When they are strictly relying on light for nutrients, they bubble up to increase surface area and capture more light.
I had my nems for a year in my main display where they were broadcast fed mysis daily with the rest of the tank. In that entire year, I could never get them to bubble, just the occasional "fat tentacles" where they look more like chubby little fingers than bubbles.
After moving them to their own tank with the clowns, and only feeding tdo pellets to the fish, they have never looked better. Par, spectrum, water quality, and flow are more or less the same. The only difference I can see is that they are no longer eating (the clowns are not feeding them either).
Just thought I'd share my experience.