What is this stuff?

Caspio · Mar 7, 2024

This looks like green hair algae, but would like confirmation before I start treating the wrong thing. Also, based on the images and info below, what you would recommend I do to fix this?

I have a 13.5 gallon tank (Fluval Evo) that's been running for about 3 months. I started with dry rock and live sand. The tank contains a clown fish, a jar of 5280 pods (AlgaeBarn), 2 red leg hermit crabs, and a couple of corals (I know, likely too early for corals but the zoa's have been spreading). A month ago I increased the daily amount of phytoplankton I was feeding and within a couple of days started to notice the green stuff on the rocks (not what I think is hair alage, the other stuff in the images), so I've since cut back. The clown fish is fed frozen brine shrimp, but he doesn't always see it so I'm certain I'm over feeding him. I've kept up with 20% weekly water changes. Regarding testing, salinity is 1.025, calcium is 420, carbonate hardness is 9, phosphate < 0.25, and nitrate is 0 (I'm using the API reef master test kit and plan on replacing it with something better when it's done). For filtration I use a pad, chemi-pure blue, and bio balls.

dethomas93 · Mar 7, 2024

Looks to me like hair algae. Your phosphates are a little high and your nitrate are non existent haha I'd raise those a bit just for water quality but a lawnmower blenny will take care of that. Just make sure you have somewhere for him to go afterwards because they can eat all the algae then starve.

Sophie"s mom · Mar 7, 2024

Caspio said:
This looks like green hair algae, but would like confirmation before I start treating the wrong thing. Also, based on the images and info below, what you would recommend I do to fix this?

I have a 13.5 gallon tank (Fluval Evo) that's been running for about 3 months. I started with dry rock and live sand. The tank contains a clown fish, a jar of 5280 pods (AlgaeBarn), 2 red leg hermit crabs, and a couple of corals (I know, likely too early for corals but the zoa's have been spreading). A month ago I increased the daily amount of phytoplankton I was feeding and within a couple of days started to notice the green stuff on the rocks (not what I think is hair alage, the other stuff in the images), so I've since cut back. The clown fish is fed frozen brine shrimp, but he doesn't always see it so I'm certain I'm over feeding him. I've kept up with 20% weekly water changes. Regarding testing, salinity is 1.025, calcium is 420, carbonate hardness is 9, phosphate < 0.25, and nitrate is 0 (I'm using the API reef master test kit and plan on replacing it with something better when it's done). For filtration I use a pad, chemi-pure blue, and bio balls.

That is indeed hair algae. You need some nitrates. feed your fish more so they will come up. The general thought is a 10:1 ratio. So if your phosphates are .25, then your nitrates should be 25ppm. What is your CUC? There are many critters that will help control algae, but you need nitrates above zero. Hopefully someone with more in depth knowledge will come along.

Jekyl · Mar 7, 2024

This looks like normal progression for starting with dry rock. Don't attempt to completely eliminate as this is normal progression.

Definitely need to add some CuC though. I would check out reefcleaners.org. Their cleaner packages are too big for your tank but you can see the variety that is encouraged and order accordingly.

As others have mentioned keep nitrate above zero. 10 is probably a good range to shoot for.