Tiny Jellies?

[slipperyslope]

The population of these guys has exploded today in my 1.5 gal reef tank. I siphoned some off into a test tube. What are they?

 

[rayadog]

That’s really cool! Neat catch! I’m jealous of such an interesting find. [I just refound my chiton so that’s all I’ve got going for me]

I think you have medusa stages of hydroids; er that’s my take. How old is this little tank?

 

[EnterName]

Yepp, Hydroid medusoid. See page 3, post #51 of my microscopy thread. They will most likely disappear after some time on their own. They appear mostly in new tanks, but if you upgraded tanks or moved everything into a new system they can also appear in my experience.

You might also notice some tentacles soon (see page 4, post #61) or these guys (see page 4, post #80). Both can irritate corals which is annoying. The tentacles will probably also disappear on their own while colonial hydroids might require you to become active depending on species.

 

[slipperyslope]

That’s really cool! Neat catch! I’m jealous of such an interesting find. [I just refound my chiton so that’s all I’ve got going for me]

I think you have medusa stages of hydroids; er that’s my take. How old is this little tank?

It’s one of my favorite parts about getting into saltwater, finding all the little creatures!

My tank is just over two months old now.

 

[slipperyslope]

Yepp, Hydroid medusoid. See page 3, post #51 of my microscopy thread. They will most likely disappear after some time on their own. They appear mostly in new tanks, but if you upgraded tanks or moved everything into a new system they can also appear in my experience.

You might also notice some tentacles soon (see page 4, post #61) or these guys (see page 4, post #80). Both can irritate corals which is annoying. The tentacles will probably also disappear on their own while colonial hydroids might require you to become active depending on species.

Awesome posts! How do I know if they are becoming an issue? Currently battling dinos with hydrogen peroxide and nutrient dosing. I am surprised the hydroids are thriving considering the h202. I only have one coral and it’s a pulsing xenia. It’s looking sad but still alive, not sure if it’s the lack of nutrients or something else.

 

[EnterName]

Yepp, Hydroid medusoid. See page 3, post #51 of my microscopy thread. They will most likely disappear after some time on their own. They appear mostly in new tanks, but if you upgraded tanks or moved everything into a new system they can also appear in my experience.

You might also notice some tentacles soon (see page 4, post #61) or these guys (see page 4, post #80). Both can irritate corals which is annoying. The tentacles will probably also disappear on their own while colonial hydroids might require you to become active depending on species.

Awesome posts! How do I know if they are becoming an issue? Currently battling dinos with hydrogen peroxide and nutrient dosing. I am surprised the hydroids are thriving considering the h202. I only have one coral and it’s a pulsing xenia. It’s looking sad but still alive, not sure if it’s the lack of nutrients or something else.

Thank you for the kind words take a look around the thread there are many more interesting creatures.

H2O2 dosing is a very experimental approach. The second it enters your tank you are just oxidizing whatever the few mL of H2O2 hit. You may increase the oxidation state of certain trace elements or react with some organics, but it's not like the H2O2 waits and then reacts with dinoflagellates itself and destroys their cells.

The reason why H2O2 may have an effect as you are changing a bit of water chemistry and even small changes can make a big difference long-term with respect to the microbiology. If you have an ORP sensor you will also notice that a few hours after dosing (sometimes even only minutes depending on amount) the ORP is back to normal so there probably is very limited long-term effect at all when not dosing very frequently. It's not unlikely that the effect some people reported on dinos was just coincidence.

Medusoids and digitate hydroids rarely stay for long in tanks. You will see them for a year or two and then they are usually gone. The colonial hydroids are different. They can very well become an issue but this depends on species.

 

[slipperyslope]

Thank you for the kind words take a look around the thread there are many more interesting creatures.

H2O2 dosing is a very experimental approach. The second it enters your tank you are just oxidizing whatever the few mL of H2O2 hit. You may increase the oxidation state of certain trace elements or react with some organics, but it's not like the H2O2 waits and then reacts with dinoflagellates itself and destroys their cells.

The reason why H2O2 may have an effect as you are changing a bit of water chemistry and even small changes can make a big difference long-term with respect to the microbiology. If you have an ORP sensor you will also notice that a few hours after dosing (sometimes even only minutes depending on amount) the ORP is back to normal so there probably is very limited long-term effect at all when not dosing very frequently. It's not unlikely that the effect some people reported on dinos was just coincidence.

Medusoids and digitate hydroids rarely stay for long in tanks. You will see them for a year or two and then they are usually gone. The colonial hydroids are different. They can very well become an issue but this depends on species.

The h202 seems to be working for me. I went that route since I have it on hand and don’t have anything else, I had to buy nutrients to dose.

The dinos were horrible covering everything for about a month and only started clearing up when dosing h202. I dose twice a day and when I miss a window, they start coming back.

I am hoping the nutrients provide the buffer to keep the dinos away for good but we shall see!

 

[EnterName]

Thank you for the kind words take a look around the thread there are many more interesting creatures.

H2O2 dosing is a very experimental approach. The second it enters your tank you are just oxidizing whatever the few mL of H2O2 hit. You may increase the oxidation state of certain trace elements or react with some organics, but it's not like the H2O2 waits and then reacts with dinoflagellates itself and destroys their cells.

The reason why H2O2 may have an effect as you are changing a bit of water chemistry and even small changes can make a big difference long-term with respect to the microbiology. If you have an ORP sensor you will also notice that a few hours after dosing (sometimes even only minutes depending on amount) the ORP is back to normal so there probably is very limited long-term effect at all when not dosing very frequently. It's not unlikely that the effect some people reported on dinos was just coincidence.

Medusoids and digitate hydroids rarely stay for long in tanks. You will see them for a year or two and then they are usually gone. The colonial hydroids are different. They can very well become an issue but this depends on species.

The h202 seems to be working for me. I went that route since I have it on hand and don’t have anything else, I had to buy nutrients to dose.

The dinos were horrible covering everything for about a month and only started clearing up when dosing h202. I dose twice a day and when I miss a window, they start coming back.

I am hoping the nutrients provide the buffer to keep the dinos away for good but we shall see!

If it seems to work and doesn't harm anything, keep it going. Unfortunately not everyone has success with this method, but I'm happy if it is helping you. It's a cheap and easy way when it works.

Keep us posted how the situation progresses