White/clear, liquid/film, Floating at the top of the water

[PygmyMitch]

can someone help me identify what this is ?

 

[PheonixKingZ]

It’s commonly called biofilm.

Do you have a lid/hod on your tank?

It is caused by partials in the air landing on the surface of the water.

Here is a more technical explanation: “A biofilm forms when certain microorganisms (for example, some types of bacteria) adhere to the surface of some object in a moist environment and begin to reproduce. The microorganisms form an attachment to the surface of the object by secreting a slimy, glue-like substance.”

(https://www.cs.montana.edu/webworks...ters/chapter001/section002/green/page001.html)

It is not dangerous to fish, just try to remove it with a fine net. If you want to prevent this, I suggest you get a lid/hood for your tank.

 

[Byron]

Agree as to what it is, a bio-film that when on the surface is often referred to as protein film. It comes from proteins released from fish foods, and also DOC (dissolved organic carbons). It is more frequent sometimes in planted tanks because of the increased nutrients. Though initially not problematic, it can become dangerous if it increases to the point of retarding the normal gas exchange (oxygen in, CO2 out).

There are several ways to reduce/remove it. Limit the organic load (don't overcrowd fish, don't overfeed, regular substantial water changes). A skimmer attachment to the filter (depends upon the filter) will pull surface water in. Increasing the surface disturbance from the filter will help prevent it. During the water change, invert the water changer so it pulls water off the surface [it takes a bit of trial and error to get this working effectively]. Laying paper towels on the surface and carefully lifting them off is sometimes suggested but I had no luck with this and it wastes a lot of paper towels.

I have only had this in one tank, the tank that for some reason had high organics.

 

[PheonixKingZ]

I have it from time to time, it’s nothing to worry about really.

 

[CassCats]

Lack of surface agitation can cause it too. I get it in my betta tanks who have a lot of floating plants so there is a lot of "still" areas on the surface between the plants where the filters dont disturb.

 

[PygmyMitch]

Yes mate i have a lid. im still in the early stages of setting it up. been taking the wood and ornament out of the tank as the wood was leaking the tanning. which at first i didn’t know about. but i’ve got that under-control now. Thanks for the info

 

[CassCats]

Charcoal in the filter will remove the tannins from the wood if you dont want them

 

[PygmyMitch]

Charcoal in the filter will remove the tannins from the wood if you dont want them

Thanks mate, i’ll give that a try if my current method doesn’t work