Any idea what this is??

[waveland]

Hey all,

I have a Fiji Cube 11 with a Aqueon 20 high sump that I baffled with an eBay kit.  It's been up about 2 months and I love the stability I'm seeing with a nano display and a larger sump.  I've seeded copepods and have cheato growing in the center chamber.  Anyhow, I noticed this little guy on the sump glass last night.  About a couple mm in length and sliding on the glass like a slug.  Any thoughts?

[Firefish15]

Appears to be some type of flatworm. Could be benign, could be a pest. I’d treat it with caution.

[seabass]

Definitely a flatworm.  Can you get a clearer picture of it?

[Sturgi_0225]

Look like a FW…. Try and find a blue sapphire damsel, they are very docile and will help eradicate the flat worms in a month or so then keep around or pass along to another reefer  

[waveland]

Thanks all for pointing me in the right direction.  The flatworm was in my sump and I haven't seen it since.  None the less, I now know what it is and will be monitoring it's growth/reproduction.  Always something in this hobby, lol😎

[mcarroll]

FYI now is usually "too soon" to grow chaeto......it's generally intended to "mop up" excess nutrients left from feeding the fish in an established system.

 

Added too soon, "best case scenario" most of the time is the chaeto starves (it's a fast growing algae that requires large amounts of N and P) and it dissolves into the tank.  You're out $10.

 

Less likely, but possible, it can crash a tank or trigger a hair algae or even dino bloom.