[Plantmytank]

It's a 4 years old 10 gal RCS tank. About 2 months ago I've noticed this brown/black stuff growing on the back glass of the tank. Have to admit that for the last few months I didn't keep up with water changes too well. Now I change the water as I did in the begging, about 20% every 2 weeks. I have about 100 RCS and feed them every other day.
What kind of algae is this and how to get rid of it?
Thanks.

 

[dukydaf]

I cannot clearly see due to all the reflections. Is it like a slime ? how easy is it to remove (just drag the finger, rub with sponge, get that razor out). Is it like a mat or does it grow in small tuffs ?

From what little I can see I would go with BGA - cyanobacteria. It can grow in floating mats and near the waters age. It also grows on the substrate. Looks similar to what you have ?

 

[Plantmytank]

The green stuff could be BGA but what is the black one? I try to scrape it off with a credit card and it's not like it's falling apart on it's own, you have to put some effort. But ones it gets off it's kind of sticky/spongy thing. It easily falls apart ones it's not attached to anything anymore. It sticks to the plants, glass, gravel.

 

[dukydaf]

Hmm, try to spot dose a little excel on a part covered with the black one with the filter off. Does it turn pink or white ?

I have seen this very fine type of BBA? in low tech tanks that may fit your description /algae. It is like a velvet mat.

 

[Plantmytank]

I don't have excel unfortunately. Forgot to mention that the algae was about 3mm long when I scraped it off. When I first saw it I though well, it is time to replace the bulb. I replaced it with a new one and it still grows.

 

[dukydaf]

Yes, sounds like the type of bba I have in mind. Do you have some hydrogen peroxide? You can also use it to treat.

From the looks of it, the infestation is severe enough to require a whole tank treatment. It needs to be physically removed when possible and active treatments. Once it grows it is very hard to get rid of just by modified tank parameters.

Sent from my HTC One using Tapatalk

 

[Plantmytank]

So I guess I have to inject H2O2 locally, right? What do you mean by whole tank treatment? I will have to remove all the shrimp, plants, etc? And if I do it locally will it change the water parameters in the way that it's gonna kill my shrimp?

 

[Kathyy]

Before zapping it remove it manually. Drop the water level below it and scrape the glass with a new razor blade if the credit card didn't work well. I'd put a paper towel down to catch if your hand drops any.

Zapping is better used when the plants are involved. It's easy to get any kind of algae off tank walls.

I had a monster CB/GDA and maybe GSA mat on my tank a year ago due to neglect/stagnant water in that spot then too much light, wiped it off and it didn't return. I looked at the nasty thing for about a month to see if it would die but it just got uglier so I took a number of paper towels and wiped it off when the water level was low. I managed to avoid dropping any of it into the water somehow. There was some GSA under it that I rubbed off with my usual Mr. Clean sponge as the tank is acrylic, no razor blades allowed. I hope that once the mat is gone and you have cleaned up the tank it won't return.

 

[Plantmytank]

Before zapping it remove it manually.

Will do that. What about the plants? Is there a way to get it off?