Bloom

[NailsInside]

Any ideas as to why I'm suddenly having a bloom of this algae?

 

[saltwater sam]

It might be helpful to post some parameters and give some background info?

 

[NailsInside]

Couldn't agree more Sam

Tank parameters

Temp: 27.6 Celsius (81 Fahrenheit)

Salinity: 1.025
Mag: 1200ppm
Calcium: 420ppm
kH: 9dkH

Over the last month I've upgraded my skimmer to a deltec sc1455 and also changed my dt flow through the subtraction of my 2x Koralias to a wp25 (more than enough flow now). I do wc's religiously 15-20%/w, I recently (maybe a week or so ago) added that rock in the first pic,

That all I can think of atm. The tank has been running for about +10 months now I think.

 

[Psirex]

I would say the rock is leeching something into the water, when was the last time you change your water filters\RO-DI?

 

[BigJohnny]

Couldn't agree more Sam

Tank parameters

Temp: 27.6 Celsius (81 Fahrenheit)

Salinity: 1.025
Mag: 1200ppm
Calcium: 420ppm
kH: 9dkH

I recommend you get a new Magnesium test kit (actually I recommend you get a new alk/magnesium/nitrate/phosphate test kit, the API Calcium is fine).

Either your test kits are off or you have low mag at 1200. Should be 1285-1350 with 420 Calcium and 9 dkH sustained.

Over the last month I've upgraded my skimmer to a deltec sc1455 and also changed my dt flow through the subtraction of my 2x Koralias to a wp25 (more than enough flow now). I do wc's religiously 15-20%/w, I recently (maybe a week or so ago) added that rock in the first pic,

That all I can think of atm. The tank has been running for about +10 months now I think.

If it's only on that new dry rock, it's just diatom/new tank algae. I wouldn't freak out thinking it's "leaching something". It's only been one week. Fresh dry rock is the first place things will grow in a tank because it's brand new and equilibrium with the rest of the tank has not been reached.

Give it some time and see what happens. If it doesn't go away or changes into a big nuisance algae problem OR you suddenly have elevated sustained phosphate without changing anything else, then you can start to worry about "leaching". For now it looks normal to me.

 

[Fish_BowLisha]

I recommend you get a new Magnesium test kit (actually I recommend you get a new alk/magnesium/nitrate/phosphate test kit, the API Calcium is fine).

Either your test kits are off or you have low mag at 1200. Should be 1285-1350 with 420 Calcium and 9 dkH sustained.



If it's only on that new dry rock, it's just diatom/new tank algae. I wouldn't freak out thinking it's "leaching something". It's only been one week. Fresh dry rock is the first place things will grow in a tank because it's brand new and equilibrium with the rest of the tank has not been reached.

Give it some time and see what happens. If it doesn't go away or changes into a big nuisance algae problem OR you suddenly have elevated sustained phosphate without changing anything else, then you can start to worry about "leaching". For now it looks normal to me.

+1. relatively new tank