Thick biofilm over tank 24 hours

[luke4868]

Hi, I started a fish in cycle 24 hours ago and this odd biofilm has appeared all over the wood in the tank. It seems thick and a film has appeared on the surface too. Please see images from google drive in link below. I've never seen it before and had several community tanks, any ideas what it could be? The fish themselves seem ok in their behavior, but worried something is happening that might affect them.

Tank size: 25L
pH: 7.2
ammonia: 0ppm
nitrite: 0ppm
nitrate: 10ppm
tank temp: 24c

Fish Symptoms (include full description including lesion, color, location, fish behavior): - Added 2 high fin danio on Sunday afternoon, seem to be fine in themselves, playful, keeping together, poking around in top-middle of tank, eating fine.

Volume and Frequency of water changes: - 25% water change and dechlorinated.

Chemical Additives or Media in your tank: - Started a fish in cycle using API Perfect Start kit, added day 1 packets which was aquarium salt,

Tank inhabitants:2 high fin danio

Recent additions to your tank (living or decoration): added some plants and a branch from LFS just before the fish were added.

Exposure to chemicals:

Digital photo (include if possible): https://drive.google.com/drive/folders/11jK69Qi5OOtZoKMjzbu3pFY0pmQW_fTy?usp=sharing

 

[Colin_T]

Take the wood out and hose it off, then put it back in the tank.

Use some paper towels and gently rest them on the surface to pick up the scum. Or use a plastic container to drain the scum off the surface.

 

[NickAu]

Tank size: 25L

Is that a Zebra danio I see?

That fuzz you see on the wood is quite normal, just wash it off like Colin said.

 

[luke4868]

Yeah it is @NickAu

I've taken the wood out and cleaned it off, and it's currently out the tank and been drying for past 24 hours or so. Will put it back in shortly.

I cleaned all the film off the surface, but it's back again 24 hours later. I assume it's some sort of bacterial issue? the fish themselves seem fine though thankfully.

 

[NickAu]

Hi

Hate to be the bearer of bad news but your tank is way too small for zebra danios they need a tank that's at least 3 feet long.

 

[Colin_T]

There's no need to leave the wood out. Just rinse the gunk off and put it back in the tank. And remove the film from the surface whenever it appears. Eventually it will stop and you will never see it again.

 

[luke4868]

Hi

Hate to be the bearer of bad news but your tank is way too small for zebra danios they need a tank that's at least 3 feet long.

Oh really? that's a shame, I'm setting up a larger tank in the near future so they can move into that one once it's ready, this tank was intended to be a shrimp tank anyway to be honest.

There's no need to leave the wood out. Just rinse the gunk off and put it back in the tank. And remove the film from the surface whenever it appears. Eventually it will stop and you will never see it again.

Thanks colin, wood is back in now and the film seems to be sorting itself out thankfully.