Amphipods during daylight hours?!

[greg1786]

Hi guys. My current tank has been up and running just over 4 months. As soon as the cycle was complete, I added a ball of chaeto filled with various pods from LFS and bought a bottle of tiger pods and added them as well. My goal was to get a nice big pod population going before adding any fish. Needless to say it worked very well and I have tons of amphipods and copepods.

The copepods are generally visible at all hours on the glass, rocks, and free swimming. The amphipods however are generally seen few and far between during daytime hours. If I shine a flashlight in the tank after lights out, theres a ton of amphipods running around everywhere. Anyhow, my clowns came out of QT a couple weeks ago into the DT and are currently the only fish. They have made the amphipod population during daylight hours even more sparse as they actively hunt them all day long.

Now the strange part. Today I come home from work and go to the tank to feed and just observe everything. To my surprise, there are amphipods everywhere! I dont mean like more than usual but still have to look for them, I'm talking full on running rampid by the thousands. They are EVERYWHERE!! There's so many of them they are running on top of one another all over the sandbed, LR and even a bunch on the glass. Anyone ever experience something like this? I'm not concerned by the quantity of them at all I knew I had a big population as viewable by night but just concerned about why over 4 months they're never visible during the day with exception to one or two, then randomly out of seemingly nowhere, they emerge during the day in full on riot mode. The clowns wouldn't even take the mysis I tried to feed, which is NOT AT ALL like them, because they've been in smorgasbord mode a la amphipods buffet. Anyone have any advice or insight as to what could cause this? Appreciate any help you guys can offer about this strange occurance.
Thanks in advance
-Greg

 

[Gareth elliott]

Hi guys. My current tank has been up and running just over 4 months. As soon as the cycle was complete, I added a ball of chaeto filled with various pods from LFS and bought a bottle of tiger pods and added them as well. My goal was to get a nice big pod population going before adding any fish. Needless to say it worked very well and I have tons of amphipods and copepods.

The copepods are generally visible at all hours on the glass, rocks, and free swimming. The amphipods however are generally seen few and far between during daytime hours. If I shine a flashlight in the tank after lights out, theres a ton of amphipods running around everywhere. Anyhow, my clowns came out of QT a couple weeks ago into the DT and are currently the only fish. They have made the amphipod population during daylight hours even more sparse as they actively hunt them all day long.

Now the strange part. Today I come home from work and go to the tank to feed and just observe everything. To my surprise, there are amphipods everywhere! I dont mean like more than usual but still have to look for them, I'm talking full on running rampid by the thousands. They are EVERYWHERE!! There's so many of them they are running on top of one another all over the sandbed, LR and even a bunch on the glass. Anyone ever experience something like this? I'm not concerned by the quantity of them at all I knew I had a big population as viewable by night but just concerned about why over 4 months they're never visible during the day with exception to one or two, then randomly out of seemingly nowhere, they emerge during the day in full on riot mode. The clowns wouldn't even take the mysis I tried to feed, which is NOT AT ALL like them, because they've been in smorgasbord mode a la amphipods buffet. Anyone have any advice or insight as to what could cause this? Appreciate any help you guys can offer about this strange occurance.
Thanks in advance
-Greg

I would not worry unless you see an increase in any of your nutrient values. What you are probably seeing is the increase in population due related to reproduction rates and food availability. Depending on temperature and size of the males and species reproduction age is reached from 4 and 17 days at least in laboratory studies. The number of offspring then being decided by the ratio of males to females(most amphipoda species offspring are produced at higher female/male ratios, but not all) Being 4 months you are finally seeing the high point of the curve, this will most likely drop then rebound, over the life of your tank. I add new population once or twice a year to offset decreased inbred vigor.

 

[greg1786]

I would not worry unless you see an increase in any of your nutrient values. What you are probably seeing is the increase in population due related to reproduction rates and food availability. Depending on temperature and size of the males and species reproduction age is reached from 4 and 17 days at least in laboratory studies. The number of offspring then being decided by the ratio of males to females(most amphipoda species offspring are produced at higher female/male ratios, but not all) Being 4 months you are finally seeing the high point of the curve, this will most likely drop then rebound, over the life of your tank. I add new population once or twice a year to offset decreased inbred vigor.

So perhaps the increase in availability of food has spurred their reproduction rate? The timeline would make sense seeing as I was only very lightly ghost feeding a few times a week prior to adding the clowns. Now, over the last 10 plus days since the clowns were introduced I've been feeding an alternating mysis and new era pellets diet daily. With the added food source the amphipods can greatly increase their population since it can now be supported? Nutrients are not an issue atm the P04 fluctualtes between 0 and 0.04 while N03 steadily tests unreadable or 0. I just thought it odd that they showes up like this literally overnight. I'm very attentative to the tank and observe it multiple times a day so I know they were not there during daylight yesterday. Although as I said at night you can easily see them in large quantities. Anyway thanks for the reply @Gareth elliott much appreciated.

 

[jorahx]

What do you put in the tank to feed the pods?

 

[greg1786]

What do you put in the tank to feed the pods?

I don't specifically feed them. I was just noting that since I'm feeding the clowns on a daily basis now that the amphipods are getting anything left over of the mysis and pellets, that's not eaten by the clowns or nass snails.

 

[jorahx]

I ask because I bought a bottle of trisbe pods. Put them in the rock work of my tank. Saw my two clowns eating them. And haven't seen any pods since the second day. So didn't know if they died off from lack of pod food. Or clowns ate them all. Or they are just hiding. I tried using flash light at night and see none.

 

[Gareth elliott]

In the tank i dont feed them either. Easy to culture outside the tank with small amounts of phytoplankton if needed loads more. When adding pods, best to turn the skimmer off, remove filter sock and add after dark.
Give them a chance to settle then replace the socks and turn skimmer back.

 

[greg1786]

To add on to what Gareth said....which was all great points, don't try to dose phyto into the DT to feed the pods. You would need such and absurd amount of phyto to make the concentration in a large tank enough to add nutrition for baby pods it would never be worth it. Separating them into a small tank with only a few gallons of water is your best bet. The other big upside to doing so is that as the new pods hatch, you have no predation until you add them to the DT!

 

[jorahx]

Thanks for the help guys.

 

[greg1786]

Yup

 

[jorahx]

Okay so I tried it over the weekend. I turned off all pumps and skimmer and lights and emptied a bottle of pods into the tank at the bottom where the rocks are. And in the back compartment where the refug is.

I noticed my two clowns (only fish I have) eat a few. But two days later I try shining the light in the tank at night and saw no pods.

Do you guys think my clowns ate them all?

I had taken the filters out and skimmer off for 24 hours in hopes they will find. A good rock to hide in.

 

[greg1786]

Okay so I tried it over the weekend. I turned off all pumps and skimmer and lights and emptied a bottle of pods into the tank at the bottom where the rocks are. And in the back compartment where the refug is.

I noticed my two clowns (only fish I have) eat a few. But two days later I try shining the light in the tank at night and saw no pods.

Do you guys think my clowns ate them all?

I had taken the filters out and skimmer off for 24 hours in hopes they will find. A good rock to hide in.

I wouldnt dismiss them just yet. They are so tiny that it will take quite a bit of them to be easily seen in a decent sized tank. It would take an awful lot for two clowns to decimate an entire bottle of pods. Give it a couple weeks. In my most recent setup I added a bottle of pods and some chaeto to an otherwise empty tank( no fish, coral, or other inverts) and it took weeks for me to see them populate the tank. Keep checking at night. My suggestion would be to go to the corner with the least amount of flow and shine your flashlight on the front glass through the adjacent panel. So basically shine the light from the side glass onto the front glass and look that way . it helps the light hit the pods just enough that you can see an scurrying around. Once They have had time to settle in and start reproducing you should see tons of em, so long as you don't have any pod specific eaters in the tank ie mandarin, pipefish, grasses etc. Good luck keep us updated!

 

[jorahx]

today i did some cleaning of my cheeto reactor. I poured the water into a Tupperware container and shined a light in it. i saw a good amount of tiny little bugs moving around, some bigger and some smaller. maybe i have pods growing just slowly.

 

[greg1786]

today i did some cleaning of my cheeto reactor. I poured the water into a Tupperware container and shined a light in it. i saw a good amount of tiny little bugs moving around, some bigger and some smaller. maybe i have pods growing just slowly.

Glad to hear it! Keep checking and keep us updated! I took a photo today of my amphipods invasion so you could see how insane it really is. This is just a small portion of one of my overflows....imagine it everywhere! In going to make a wrasse and a pair of mandarins very happy sometime soon

 

[jorahx]

Wow! that is a lot indeed.

 

[jorahx]

Each night I have noticed 3-5 bugs roaming around the sand. Or rocks. One frag I was cutting the plug off and noticed two little bugs. Looks like I finally am building my pod population.

 

[Big G]

Yes! I had a huge explosion of gammarid amphipods in my tank. That lasted until I added a Starry Blenny to the tank. Haven't seen even one of these "bigger" bugs since. Lots of copepods, but the amphipods are no where to be seen. The Blenny is relentless, scouring the rock for pods.

 

[Susan Edwards]

My larger pods eat pellet foods... I toss in pellets for the shrimp and narsarious snails and I'll see the amphipods running off with pellets. Saw one take one off a sun coral once. I culture pods and when I add them, I do so at night, skimmer and returns off and I use a large car oil funnel to pour them into various spots of the rockwork. I leave everything off for about an hour. When I'm ready to start cycling the new 125g tank, I'll add pods I'm culturing but I'll also buy a mix to be sure I get a wide variety population. I add some phyto to the tank periodically, depending on how much I have. No success in culturing that yet. It's also good for corals.