"Dan Drake" wrote in
news:vhIsdqY67dTD-pn2-4tZMfVbxteyh@localhost:

A lot of people talk of _hair_ algae, specifically, being promoted by
high Fe concentration. I wonder if there's something to that. (But
what does it matter? If people are adding iron in order to grow
plants, they surely have algae-eating fish, and they'll never see hair
algae. If they don't have algae eaters, it's hopeless anyway.)

I have seen this in action.

One of my eels (a yellow-tailed spiny eel) dug up a laterite ball
inadvertently. I only noticed because hair algae came in like mad, fast
enough that I could see lots of stubble despite the two large and
industrious SAEs in the tank. When I buried the laterite again, the hair
algae ebbed.

~Empty
--
'You're not friends. You'll never be friends. You'll be in love till it
kills you both. You'll fight, and you'll shag, and you'll hate each other
till it makes you quiver, but you'll never be friends. Love isn't brains,
children, it's blood... blood screaming inside you to work its will. I may
be love's bitch, but at least I'm man enough to admit it.'
Spike