Oil on tank top?

[SaltyDog]

Hello All,

 

As I understand it, a film on top of the tank is a somewhat of a normal situation, but it drives me nuts.

 

The "oil" on top of the tank is without color, but it seems somewhat thick. It really doesn't bother me until my Margarita snails and Blue-legged hermit crabs seem to slow down to a crawl. Even with a powerhead stirring the surface of the water, it doesn't seem to help.

 

If I do a water change (a gallon or so a week in my 10 gallon) everything in the tank seems to become active again. So, I tried to do 2 water changes a week, at 1/2 a gallon a week, but it has helped very little.

 

The "oil" situation has seemed to get worse since adding 2-week cured Manano rock, but it has always been present.

 

Is this normal? Should I be concerned or is this okay? Would a surface skimmer be a good idea?

 

Thanks for the help.

 

(Edited by SaltyDog at 1:39 am on May 21, 2002)

[krusty]

the oil slick u are seeing, is most likely protien on the surface and an excess buildup of nitrates.... or since in the addition of LR possibly ammonia... I would recommend adding a skimmer part time or possible a surface overflow and see if that helps...

[flaunt]

for how long as your aquarium been up and running?  adding live rock after the system has established itself probably isn't the best idea, but since you've already done it i would just do water changes, every day if i had to.  i cured my own LR and i just kept changing changing and changing water until the foam went away and the ammonia/nitrite readings went to zero.  worked well.