Another cycling concern

[newfishhobbyist]

Biocube29: We just added a raw piece of shrimp last night. My husband thinks we don't need to do this b/c the LR was cured. I want to be absolutely sure we are doing the right thing. The LR from the LFS was cured already and before we put the shrimp in, the ammonia, nitrites and nitrates were all zero. We in fact DID NEED to put the shrimp in even thought the LR was cured to get the nitrogen cycle going, right?

Thanks!

 

[roka64]

Maybe, maybe not. If you don't see ammonia in 4 days you should be cycled from the LR.

 

[melosu58]

If your LR is cured you probably wont see a big jump in ammonia or nitrite. You probably could have gotten away with the dieoff from your LR.

 

[newfishhobbyist]

How do we know if it is cycled when we have zero ammonia, nitrites and nitrates (before shrimp)?
Should we take the shrimp out?

 

[Kurt_Nelson]

If the rock was indeed cured, then keeping the shrimp in will do no harm. It will decompose, giving you ammonia, which your cured rock will quickly convert to nitrites and nitrates. Keeping the shrimp in there, you'll know the rock was cured if nitrates begin to show up. (That assumes you started with nitrate-free water.)

 

[newfishhobbyist]

Thank you. I feel much better. The water was nitrate free before the shrimp.

Now, one more concern. We have a couple of snails, small starfish and feather duster tubeworms. Will this shrimp process kill them off?

Thanks again!

 

[Kurt_Nelson]

Depends on if the rock was cured or not. If it was cured, then you won't see a cycle - you'll just see nitrates showing up meaning your tank is ready for critters. If it wasn't cured, then you'll see a cycle and the critters will be at risk.

 

[newfishhobbyist]

Thanks. Do you recommend doing water changes?

 

[melosu58]

PWC`s will slow down the cycle but if you want to keep those inverts alive you will need to do some. Nothing should be in the tank during the cycle.

 

[roka64]

I agree, plus the shrimp will give your clean up crew some extra snacks!

 

[Kurt_Nelson]

I wouldn't do water changes unless you start seeing ammonia show up. The whole point is to see if nitrates show up without the accompanying ammonia/nitrites. And doing water changes at this point only dilutes the things you're trying to measure.

 

[newfishhobbyist]

We tested the water last night, after 24 hours of having the shrimp in the tank. Ammonia and nitrites were both zero; nitrates were at 5. Is this a good sign? Thanks again...you guys are great!

 

[Kurt_Nelson]

Yup... good sign. Sounds like your rock was truly cured and you have a cycled tank!

 

[melosu58]

Sounds like it to me also.

 

[newfishhobbyist]

Awesome! With that being said...should we still keep the shrimp in the tank until it's gone?

 

[thincat]

PWC's will as Mike stated save most of your critter and also the animals in your LR. Doing PWC will not harm your tank in any way. Most of your bactria are in your rock and sand.
Leave the shrimp in, it will feed your tank, until you get some fish and or corals.

 

[Kurt_Nelson]

I'd take the shrimp out - it served its purpose. All it will do now is continue to pollute your tank with nitrates. Since you did measure nitrates, then yeah... a water change is in order to reduce the nitrates as much as possible before adding more critters. Two or three 25% PWCs should bring them down pretty good.

[Edit: thincat snuck another line in there after the bell! Regarding leaving it in or out, if you don't plan on adding any fish for several weeks, then yeah - like thincat mentioned, leaving it in will help keep the bacteria "fed". Nitrifying bacteria, if left without an ammonia source (like fish poop, fish respiration, excess food, eetc), will die off, leaving your once cycled tank now back at square one. But if you're going to add fish right away, no need to leave the shrimp in.]

 

[thincat]

Sorry for the low blow...