# Strange black tar



## cliff1858 (Jun 5, 2012)

Hello everyone, glad I found this place! 

I am into aquariums but that is not what brings me here today. I am working on a photography project and using a 70 gallon fish tank for it. I am using an Aquaclear 70 water filter for filtration. A black tar keeps showing up on the bottom of the fish tank for some reason. Is it time for a new water filter? Maybe it has something to do with no plants or fish living in the tank? 

I took the filter apart and the layer under the white rocks looks like its causing the problem. Is this a needed piece of the filter for how I am using it? (nothing in the tank) I do need the water to very clear for the photos. Also peoples heads will be going in and out of it. 


I am a complete noob here so any input would be awesome!


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## Reefing Madness (Aug 12, 2011)

Fresh Water Tank or Salt Water? A power filter would probably work better for you, being as its gph capabilities are much higher.


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