How does the BBA spread?

[Victor Cheong]

Hi all

Let us assume that plant X has BBA growing on it, will BBA spread to the nearest plant first based on the proximity? Thks!

[milk_vanilla]

Not always, it will attack your weakest plant first according to my observation.

[Urban Aquaria]

Yeah, they usually get introduced by hitchhiking with plants into tanks, then the spores and filaments get carried by filter currents to spread around the tank.

The spores and filaments will attach to any tank, equipment, hardscape or plant surface and grow there when conditions are ideal, in most cases its usually on plants which are weak (like what milk_vanilla mentioned) or melting, all the extra nutrients from rotting plant matter released back into the water column fuel the BBA growth in those areas. Healthy fast growing plants seem to have some natural defense against the algae, thats why often times people see a bunch of plants covered in BBA, yet other bunches of plants sitting next to them have no BBA.