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Oil Slick in your Fish Tank

oil slick

When we talk about an oil slick in your fish tank we don’t mean something like the disaster of the above photo which was the terrible event of the BP Deep-water Horizon rig in Gulf of Mexico explosion of 2010.

What I mean is the oil slick you get in you Tropical fish aquarium. I know this isn’t anything like the above but is still a question worth answering.

oil slick 2

I talk from personal experience and had what can only be described as an oil slick on my fish tank for a couple of months . I changed 50% of the water every week and tried reducing food given, I also increased surface flow by installing a couple of power heads but nothing seemed to shift it.

When I was on the verge of giving up I realised there was one final thing to try. I reduced feeding some more and introduced a few air lines to properly break up the surface slick . I also started doing 3-4 days worth of 50% water change and clean out the filter. When I was doing the water change I was also skimming the surface to remove the slick. This seemed to finally do the trick.

What I have to come to realise is that in theory it will only come back if you are over feeding or if your fish are dying and giving off oil/chemicals and they are trapped or hidden under rocks. There are various methods you can try using to lose the oil slick which include:

  • Powerheads
  • Air Lines with air stones
  • Surface movement from filter outlets
  • Reduce feeding
  • Check no dead and decaying fish are hidden in among the décor

When you have covered all the above areas you should be oil slick free and have a healthier and cleaner looking tank!