Copepods VS. Tank maintenance

[Heather w]

I am actively seeding my tank with Copepods in anticipation of finding a nice fat mandarin in my fish shopping wanderings. I don't want to find one and have my tank lacking in them in case it won't eat frozen food from the get go. In other words I don't want to bring it home so it can starve to death before my very eyes.

Enter partial water change and substrate vacuum. How many am I sucking up and dumping down the toilet? It's not like we give the little guys warning so they can pack up and get out of town before we suck up their neighbors.

What is the greater evil, so to speak? I have no idea how many are in my tank to begin with. How can I tell if there is enough so I don't kill another mandarin? Should I not vacuum the substrate? Am I making any sense at all?

 

[saltyphish]

Some people are against vacuuming the sand bed and others are for it. Thats a personal decision. I do stir mine up a bit when doing water changes. Depending on system size you probably arent getting that many. The size of the system and other tank inhabitants will help you determine if your ok. Mandarins arent the only fish that eat pods and other fush could outcompete it for food.

 

[MasterBacon]

A flashlight after lights are off for a while will help you see your population. Do you have a sump or refugium where they can re-populate in peace?

 

[Brew12]

Some people are against vacuuming the sand bed and others are for it. Thats a personal decision. I do stir mine up a bit when doing water changes. Depending on system size you probably arent getting that many. The size of the system and other tank inhabitants will help you determine if your ok. Mandarins arent the only fish that eat pods and other fush could outcompete it for food.

I think peoples choice of CuC also comes into play. If you have snails or other critters to help stir up your sand bed you don't need to worry about vacuuming it out as much.

 

[Bozoman]

If you want to build up a population of pods to anticipate a mandarin you want to do it in a refugium, not the display. The mandarin will eat a pod every second when the light is on if it can. That means you need a massive population that spawn continuously in a safe location or the mandarin will eventually deplete the pods in your tank and starve. It will happen, unless you tank is huge and you don't keep wrasses, anthias, etc who also eat a lot of pods.

But vacuuming the sand, where most pods will live is not a good idea if you're trying to build a population. Keep the pumps going and siphon water mid-tank to minimize the amount of pods you extract. When you turn off the circulation pods will come out more and enter the water column.

 

[Heather w]

A flashlight after lights are off for a while will help you see your population. Do you have a sump or refugium where they can re-populate in peace?

I have a 20 gal refugium. If they are growing there then they don't do the fish any good. It's not like they can order take-out. <that would be funny though, right!>sorry. I'm REALLY tired.

 

[Heather w]

If you want to build up a population of pods to anticipate a mandarin you want to do it in a refugium, not the display. The mandarin will eat a pod every second when the light is on if it can. That means you need a massive population that spawn continuously in a safe location or the mandarin will eventually deplete the pods in your tank and starve. It will happen, unless you tank is huge and you don't keep wrasses, anthias, etc who also eat a lot of pods.

But vacuuming the sand, where most pods will live is not a good idea if you're trying to build a population. Keep the pumps going and siphon water mid-tank to minimize the amount of pods you extract. When you turn off the circulation pods will come out more and enter the water column.

 

[DanP-SD]

A healthy pod population in a refugium will do the fish a lot of good. The pods make their way from the refugium to the DT and continuously re-supply the tank. The idea is that the refugium creates a place where your mandarin can't eat them -- like if you had a corner of the tank it couldn't reach. That we it can only deplete a portion of the pod population (those in the DT). That doesn't mean the mandarin can't starve to death. Once it depletes the DT population the number of pods making it from the refugium to the DT may not be enough. One way to help with that is to periodically boost the colony by adding more pods to the refugium and, from time to time, preferably after dark, taking some of the chaeto or caulerpa from the the refugium (hopefully loaded with pods) and seeding the DT.

 

[Heather w]

But again. If they grow in the refugium what good does that do when the fish are in the display tank?

A healthy pod population in a refugium will do the fish a lot of good. The pods make their way from the refugium to the DT and continuously re-supply the tank. The idea is that the refugium creates a place where your mandarin can't eat them -- like if you had a corner of the tank it couldn't reach. That we it can only deplete a portion of the pod population (those in the DT). That doesn't mean the mandarin can't starve to death. Once it depletes the DT population the number of pods making it from the refugium to the DT may not be enough. One way to help with that is to periodically boost the colony by adding more pods to the refugium and, from time to time, preferably after dark, taking some of the chaeto or caulerpa from the the refugium (hopefully loaded with pods) and seeding the DT.

That is a wonderfully understood explanation! Thank you!

 

[MasterBacon]

But again. If they grow in the refugium what good does that do when the fish are in the display tank?

That is a wonderfully understood explanation! Thank you!

That's given they live through the dreaded return pump of hello- o

 

[Salty1962]

You shouldn't suck that many out during a water change, even if they go to the water column they will go into hiding rather quickly. I wouldn't scrape my glass and then do a water change to help eliminating as many. They also will reproduce quickly if you keep them fed

 

[Sabellafella]

I am actively seeding my tank with Copepods in anticipation of finding a nice fat mandarin in my fish shopping wanderings. I don't want to find one and have my tank lacking in them in case it won't eat frozen food from the get go. In other words I don't want to bring it home so it can starve to death before my very eyes.

Enter partial water change and substrate vacuum. How many am I sucking up and dumping down the toilet? It's not like we give the little guys warning so they can pack up and get out of town before we suck up their neighbors.

What is the greater evil, so to speak? I have no idea how many are in my tank to begin with. How can I tell if there is enough so I don't kill another mandarin? Should I not vacuum the substrate? Am I making any sense at all?

Well if your like me, and leave your filter socks in a 5 gallon bucket to eventually sit there at the end of the month with a turkey baster trying to save every cope amphipod there is because your feel bad killing them, then no it wont be a problem. Ive had copepods breed in a container that i use to cure dry rubble rock just from syphoning tank water into it. Once there in, they breed like madd, i dont think sand cleaning will effect the population.