Black algae!

[Heimao]

Hi!
My betta's ornaments (I don't have any live plants in there) are turning black. I tried scrubbing it off, but that didn't work. It is a five gallon, the temp is 78 and the ph is fine-according to petsmart. Max seems fine, but is a little lethargic. If it is black brush algae, how can I safely treat it?
Thank you!!

 

[FreshyFresh]

You should be able to remove the decor and scrub it off. I wouldn't add anything. Just reduce the lights-on time and keep up on large weekly water changes.

 

[Heimao]

I actually tried scrubbing it with water and steel wool with no luck, maybe it's because they are plastic? I cut down lights on time to five hours, and just did a 50% water change yesterday. I heard that hydrogen peroxide will remove the stains-scrubbing outside of the tank-but I am terrified of leaving residue.

 

[myswtsins]

Algae happens but it's Interesting that the white gravel has no algae! Temperature and pH don't have a big effect on algae. What does is light and other nutrients. What type of light are you using? What wattage? How often to do usually do water changes? Do you know your nitrate levels?

Peroxide is perfectly safe to use outside the aquarium. You can even use it IN the aquarium but we don't need to get into that right now. lol

 

[Heimao]

I know, it's crazy that the gravel is white! Not sure about the wattage, but it's not as bright as my big tank. I'm going to petsmart today, I'll have them check the nitrates. I do water changes once a week- I've been doing up to 50%, trying to clear it up. Thanks! I'll scrub them down with peroxide, and see if I can get rid of it, since it's only on my ornaments!

 

[fishorama]

How long are your lights on? Peroxide is especially safe on fake décor. Take each piece out & dip in straight hydrogen peroxide (the kind for the drugstore near bandaids, it's cheap & effective). Let sit for a while, rinse & return. Any residue is not harmful. But if you don't figure out what's going on, it'll come back.

 

[Heimao]

Thank you so much!! My lights are on for five hours a day-I feel like I'm depriving my fish, but I don't want to get them sick...

 

[dougall]

Check that your filter is clean, and you clean the gravel and such thoroughly.

Part of me wants to suggest using low-light plants, to use nutrients before algae might be able to... they are a good thing