In the above linked to page this spawning information is given
I have what I believe are brown hoplo but the spawning is not the same!species_id=394 wrote:Males build floating nests in vegetation near shore that consist of bubbles covered with plant material. Eggs are released by the female below the nest. The male fertilizes them and then takes them into his mouth and blows them up into the floating nest. Breeding males develop enlarged, red pectoral spines with hooks at the tips that are used to defend territories against other males. The eggs hatch in about four days.
The male does build a bubble nest using whatever plant matter he can grab but the process of the actual spawning is different. The female drops to the bottom of the tank and has the fins near her vent clamped close together catching eggs as they come out. She then swims upto the nest and places them in whatever location she has chosen but they are always close together. After that she nudges at the male and they swim in circles until he takes his turn doing what I believe is fertilizing and working the nest by blowing more bubbles. This repeats over and over until the female is done. After spawning the male will immediately take over as guard for the nest pushing her away.
Spawning can occur as often as every 10 days but in my experience the spawn ends up getting eaten every other time they spawn sometimes with the female eating the eggs so aggressively the male cant keep her away. Also not 100% sure about the brown hoplo being a south american fish. It was sent to me from Florida if that helps but it looks like one to me.
I have my first successful spawn of these growing now at about 2 weeks old now. I have joked about them on another forum as being the convicts of the catfish world! Except if what I have read is correct they will be about 1-1/2 years old before maturity.