Can anyone tell me what these are?

[blocky912]

Im new to this website heard a lot good things from it, I recently started a reef tank my cycle has been done, I have gotten some diatom in my tank and I recently started to cycle my salt water to clean it up I have four scarlet hermit crabs and three snails, I recently added some tigger pods and I notice I that seen this little worm types all over my glass, does anyone know what these are? Should I be concerned?

 

[reefsaver]

Welcome to Reef2Reef!

When starting a tank, it's absolute war in there, organisms take off, die off and bloom.
These look like brown flatworms, googlable, and I don't think they're bad. When I started my aquarium over 3 years ago and was maybe a couple months deep into cycling, I actually ran into these same brown flatworms. I didn't actively seek out their demise but over time their populations just dwindled and dwindled until they were all gone. As your system matures, more organisms that will compete with these for survival will likely be their end and manually removing what you can is probably going to speed it up a little.
I would say buy a nice Zoanthid covered live rock that's a good size to introduce a litany of biodiversity to streamline that maturing process and introduce competition for them, but I would also warn that it's each to their own and Reef aquariums are rather sterile in the first year so you could take a more scientific approach and introduce exactly what you want to the aquarium and slowly build that biodiversity the exact way you want, or you can go a more simplified way and let the war play out. I would personally choose war but yeah it's each to their own. I probably wouldn't use chemical flatworm kilers because who knows what these things will pollute into the water if they all die simultaniously. Best to just let it run it's course IMO. But I would be interested to also hear what others think. If it gives you any peace of mind at all, I did have thousands of these for maybe a month before the pops started to dissipate and eventually dissapear altogether, and that was just with time.

 

[blocky912]

Welcome to Reef2Reef!

When starting a tank, it's absolute war in there, organisms take off, die off and bloom.
These look like brown flatworms, googlable, and I don't think they're bad. When I started my aquarium over 3 years ago and was maybe a couple months deep into cycling, I actually ran into these same brown flatworms. I didn't actively seek out their demise but over time their populations just dwindled and dwindled until they were all gone. As your system matures, more organisms that will compete with these for survival will likely be their end and manually removing what you can is probably going to speed it up a little.
I would say buy a nice Zoanthid covered live rock that's a good size to introduce a litany of biodiversity to streamline that maturing process and introduce competition for them, but I would also warn that it's each to their own and Reef aquariums are rather sterile in the first year so you could take a more scientific approach and introduce exactly what you want to the aquarium and slowly build that biodiversity the exact way you want, or you can go a more simplified way and let the war play out. I would personally choose war but yeah it's each to their own. I probably wouldn't use chemical flatworm kilers because who knows what these things will pollute into the water if they all die simultaniously. Best to just let it run it's course IMO. But I would be interested to also hear what others think. If it gives you any peace of mind at all, I did have thousands of these for maybe a month before the pops started to dissipate and eventually dissapear altogether, and that was just with time.

Thanks for replying, you actually helped a lot I thought I messed up my cycle along the way. I’ll make sure to keep on eye on them see if they start to over populate, also do you know anything about wrasses? I heard they eat these flatworms any thoughts?

 

[Biokabe]

Thanks for replying, you actually helped a lot I thought I messed up my cycle along the way. I’ll make sure to keep on eye on them see if they start to over populate, also do you know anything about wrasses? I heard they eat these flatworms any thoughts?

These flatworms can easily overpopulate, and while they're not terribly harmful, they can cause problems in large quantities. They're like vermetid snails, in that they're not directly harmful most of the time, but the side effects (mostly mucus residue) can harm corals and other more desired life forms.

Many fish will eat them. Six-line wrasses, most Halichoeres wrasses and blue sapphire damsels (also known as Springer's damsel) are all good choices. Of those, the damsels are probably the most flexible - not a very demanding fish, not terribly aggressive, hardy, cheap, and beautiful. They also stay fairly small, so they can fit into almost any tank size. Six-line wrasses have a tendency to become bullies, and Halichoeres wrasses tend to eat other invertebrates that you might like in your tank. Not nearly at the level of more problematic fishes like puffers, but it's still something to be aware of.

If the flatworms stick around and become a problem, you can get any of the fish I mentioned. Or you can just get one because you like it, and take the fact that they'll eat flatworms as a bonus.