Cycling a tank with live rock: question

[AdamHorton]

Quick question: I have a 150G tank with 30G sump/refuge that I'm starting over. Eventually I want it to be a reef tank. I want to use 250 lbs live rock as filtration, and I want to cycle the tank using that rock. Some of it was left over from my first attempt, and even though I couldn't figure out what the problem was, I wanted to kill everything on all of the live rock, so I let it sit dry for a couple of weeks, then I cleaned it off with freshwater, and I let it dry out again.

Here's my question:

Since I'm cycling the tank with LR and no other ammonia source, and since I've taken these measures to kill off everything that was on the rock, do I need to provide an ammonia source to cycle the tank? Or will the LR still take care of itself?

Thanks for your help,

 

[mdaniel2882]

Depends on how clean you got the rock. Amonia is caused by decay. If there is nothing on the rock then I would suggest using the shrimp method. I might use shrimp anyway. It is cheap and will insure a good amonia source

 

[match55]

sdo a water test without adding the shrimp and if u have high amount of ammon, then don't need any raw shrimps, if not get some raw shrimps, and as mdaniel said its cheap and insure u have good ammon source for your bacteria.

 

[thominil]

Just as the others said, I would use the shrimp too. Your rock is pretty much base rock now. If you cleaned the rock good enough, I'm doubtful there will be enough die-off to even support a complete cycle. HTH.

 

[HN1]

I agree with the others, but would use 2-3 shrimp for that size tank and amount of rock. Testing will be the only thing to give you real answers. Good luck on the new start!

 

[AdamHorton]

It didn't E-mail me like it usually does when the replies came... weird...

Anyways, thanks for the advice. I'll use shrimps to make sure there's an ammonia source. My RO/DI has been on for two days straight now and the tank is still only half full, 75 gal/day my foot

When there's enough water for the plumbing to work I'll start it up and add some shrimps. I should have pictures of the new setup at that point... maybe tomorrow or Wednesday?

 

[cabezon]

pardon the newb question, but if you killed off all the "live" of the live rock, what is going to cycle? won't you end up with a cycled tank and 250lbs of base rock?

 

[thominil]

cabezon-He is adding more live rock to seed the rock he soaked in freshwater. HTH.

 

[Kurt_Nelson]

Even if he didn't add "live" rock to seed the rock, given an ammonia source and time (4-6 weeks), that 250 lbs of dead base rock would all be "live" in the end.

 

[AdamHorton]

I actually killed everything on all of the rock, so I'm going the 4-6 week route. I'm pretty convinced that whatever happened to the tank last time was because of new LR that I added, which is why I'm being extra careful with this rock and taking the extra time.

 

[thincat]

It didn't E-mail me like it usually does when the replies came... weird...

Anyways, thanks for the advice. I'll use shrimps to make sure there's an ammonia source. My RO/DI has been on for two days straight now and the tank is still only half full, 75 gal/day my foot

When there's enough water for the plumbing to work I'll start it up and add some shrimps. I should have pictures of the new setup at that point... maybe tomorrow or Wednesday?

What is your house standing water pressure? I believe you need at least 60# or more pressure for the 75g a day output.

 

[AdamHorton]

No sure, probably not 60 pounds. It should be done by the end of the week though.

 

[AdamHorton]

How often should I continue to add raw shrimp? They are 31-40/pound size. I started the tank with 4 on Sunday, and saw a slight ammonia reading on Tuesday (I don't expect to see anything significant for a week or so.

 

[thincat]

4 should be enough. Just set back and test the water every other day or so for Ammonia, nitrite, don't worry about PH as this will be bouncing around until your tank settles in.
Your ammonia will go to 0, then your nitrite will rise and fall to 0, then you should see some nitrates. When nitrites stay at 0 for a few days you are go to go. Add your CUC, wait a week and add a fish. You should be QT'ing your first fish a week from now.

 

[AdamHorton]

I've had the 5 surviving damsels in my QT for a while now. That tank is pretty much done cycling, since I guess on my first try the DT never cycled. I figured I'd add them in once the DT is done cycling. I guess now is about the time to post that thread where I figure out what I'm going to stock with...

 

[AdamHorton]

It's been two weeks since I added the first of the raw shrimp and I still haven't seen any ammonia reading. I added more yesterday. Is it possible that I need to seed the tank with something to start bacteria growing since I did everything I could to kill off what was there? Or will you just tell me to keep being patient?

 

[thincat]

It's been two weeks since I added the first of the raw shrimp and I still haven't seen any ammonia reading. I added more yesterday. Is it possible that I need to seed the tank with something to start bacteria growing since I did everything I could to kill off what was there? Or will you just tell me to keep being patient?

Addam, If your tank parameters reads 0 ammonia, 0 nitrites and some nitrates your tank is cycled. I would think twice about adding Any Damsels other then clowns to your tank.

 

[dhemp34]

i added 30 lbs of liverock to my 55 and it cycled itself in a week...i think its a matter of shot in the wind in my opinion...its all possible but i was successful with adding no chemicals...although my livercok came out of a tank that was set up for about 4 years tons of coraline no aptasia had snails and starfish coming out so thats a possibilty as to why...

 

[AdamHorton]

dhemp, I had a similar thing happen when I bought "pre-cycled" live rock and cured it myself. I saw the whole cycle in about 8 days.

I took measurements last night and I still have zero everything: ammonia, nitrite, and nitrate. The shrimp I put in the tank haven't even begun to rot or decompose or anything. It almost seems like there's no bacteria in the tank at all, but shouldn't there still be ammonia from the shrimp even without bacteria? What could cause this kind of thing, and what can I do about it?

This may not mean anything, but here's how I set up the tank this time: I had previously rinsed all of my LR in freshwater: this includes my 75 lbs of sand from the previous tank, the 100lbs LR I had from my previous tank, along with the 150 lbs I bought new (CaribSea Reef Rock). Since it took so long to add the RO/DI water to the tank, I put in the "dead" rock and sand in the tank as it was filling up, and I didn't add in any salt until the tank was basically full, meaning that the rock was soaking in RO/DI water for about a week before it suddenly turned into saltwater. The next day I added 4 shrimps, and two weeks after that (this past weekend) I added in 4 more shrimps. My goal was to make sure I killed anything that was on my LR, but could I really have made it so that the cycle doesn't start? I would think I'd see at least *some* ammonia reading by this point...