My Bristlenose Plecs (ancistrus) have now got three different size broods in my 75 gallon.
Decor is 14 pieces of bogwood, horticultural sand loads of plants.
They appear to need plenty of hiding places in which to breed.
I have heard of people using pieces of tubes to imitate caves.
Plecs in the wild burrow into the river banks to lay the eggs which are usually looked after by the male. 8)
