We have a problem with our brackish tank! It's a 55gallon brackish tank with two gsp's that we have had for 4 months now. All water levels are okay, nitrates are the only thing at 10.
A couple weeks ago, we noticed a brown film of slime on the top of one of our artificial plants that was poking out of the water (the slime was on the part outside the water). Well, we rubbed it off, and within the past couple of weeks, this has created a brown film of SOMETHING all over in our tank! Some days it doesn't seem like it advances at all, but others it seems like it spreads a bit more, like wildfire! It looks like compacted dust. Not puffy like mold or anything.
The tank is not completely covered, by any means-- parts of all of the plastic plants, and some of the substrate, none that we can see on the glass.
We THINK it's algae, but it's just a film, not stringy or anything.
So....
Do we have too much substrate?? (We have regular aquarium gravel and some sort of shell substrate.) It's about 2 to 3 inches deep.
How do we get rid of this "film"!?!
Will it hurt our puffers!?!
Help! And thanks!
Help! Brown algae or slime film!
- littlepuffers
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Re: Help! Brown algae or slime film!
Algae will not hurt your puffers. Because you have puffers the only way to get rid of it in your tank is to clean it by hand. Sometimes, most of the brown algae will go away on it's own with time. Snails clean it up very well but the puffers wont go for that....
Here is a topic I started about cleaning brown algae off my decor. Lot's of info about brown algae there: viewtopic.php?f=2&t=11612&hilit=+brown+algae
Here is a topic I started about cleaning brown algae off my decor. Lot's of info about brown algae there: viewtopic.php?f=2&t=11612&hilit=+brown+algae

55g-2 green spotted puffers 1 year old Nov 08!
20g-5 leopard danio,4 whiteskirt tetras, amanos, nerita snails, 2 neon tetras
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Re: Help! Brown algae or slime film!
Indeed, brown algae is completely normal for brackish tanks, especially new ones. It will eventually go away, but it will take more than 6 months, at least. It won't harm anything, but it will spread around pretty rapidly (as you've already noticed). You can technically scrub it off of your decorations, but honestly, it just keeps coming back, so you're best off just to clean the decorations as you normally would and wait it out. 
As for your substrate, yes, 3 inches is too much. If your substrate is too deep, you can develop anaerobic pockets, which could lead to instant-fish-death if the right situation occurs. This isn't to say it WILL happen, but your chances of it happening are a lot higher with deeper substrate. You should probably look to reduce it to around 1 to 1.5 inches. Just don't take all of the substrate out at once, as removing too much substrate could actually cause your tank to re-cycle, which is a much worse problem to deal with. Just take out a few scoops now and then until you're closer to 1.5 inches.
As for your substrate, yes, 3 inches is too much. If your substrate is too deep, you can develop anaerobic pockets, which could lead to instant-fish-death if the right situation occurs. This isn't to say it WILL happen, but your chances of it happening are a lot higher with deeper substrate. You should probably look to reduce it to around 1 to 1.5 inches. Just don't take all of the substrate out at once, as removing too much substrate could actually cause your tank to re-cycle, which is a much worse problem to deal with. Just take out a few scoops now and then until you're closer to 1.5 inches.
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40 gallon - Future home of Abei Puffer
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Re: Help! Brown algae or slime film!
Does this happen w/ gravel or cc?Agnate wrote:.......
As for your substrate, yes, 3 inches is too much. If your substrate is too deep, you can develop anaerobic pockets, which could lead to instant-fish-death if the right situation occurs. This isn't to say it WILL happen, but your chances of it happening are a lot higher with deeper substrate....

55g-2 green spotted puffers 1 year old Nov 08!
20g-5 leopard danio,4 whiteskirt tetras, amanos, nerita snails, 2 neon tetras
- littlepuffers
- Dwarf Puffer
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- Location: Alaska
Re: Help! Brown algae or slime film!
Thanks for your replies, everyone. We thinking about switching to live plants, which are supposed to help with the algae? For now, we are going to remove some substrate and clean the plastic items as best as we can, just so it looks better.
Is there any way to speed up the algae cycle?
With putting live plants in, are there other water paramaters to watch?
What types of live plants are best?
Also, the substrate we have is some shell stuff made to stabilize ph for cichlids, is this okay to use for gsps? Or what substrate is best?
Is there any way to speed up the algae cycle?
With putting live plants in, are there other water paramaters to watch?
What types of live plants are best?
Also, the substrate we have is some shell stuff made to stabilize ph for cichlids, is this okay to use for gsps? Or what substrate is best?