Macro algae die off

[Justiful]

I had some macro algae, fern calpura. It died off, bleached and I took it out. I have a some ideas what I did to cause it. But it is a toss up between light shock (from new light), phosphate crash, and magnesium increase.

What is the most likely culprit? Or is one of them not likely?

 

[shimps1]

You're probably better off honestly. Caulerpa is a huge pest, and will grow to cover everything in your tank. Get some less invasive species next time.

 

[SantaMonicaHelp]

It's sad to lose them. I'm sorry about this man, I hope next time everything will be ok! Cheer up!