Initial cycle

I've got a 75g with about 10g in refugiun and 10 or so in the sump. I saw a deal on some mature local live rock and bought about 50 lbs. Ran the tank about 10 days with no ammonia. After 10 days a shipment of fresh live rock from Florida (supposedly out of the water just 24 hours and kept and shipped wet) of about 50 lbs was added. That was 6 days ago. I got a little blip on the ammonia to .5ppm then back to 0. The nitrite and nitrate are still at 0. The were a few hitchhikers on the origional rock (2 snails and a hermit crab). Starting to get some algae growth and would like to start adding a cleaning crew. Is it possible that the mature live rock will keep the tank from a major cycle? How long would you wait? Thanks for the info in advance. - Paul

 

it's possible that if you have used precured lr that you will only get a very small cycle or potentially no cycle at all. It sounds like you got a 'mini' cycle when you added the new rock. Has it only been 16 days? If I were in your shoes, I would wait a little bit longer, maybe another week to make sure that your ammonia and nitrites stay at 0.

 

I agree with GuitarMan.. you could also try adding a piece of food or something to see how the levels react..

 

If it just came from the ocean it is not cured. Cured means that it has been removed from the ocean and placed in a tank to allow for whatever dieoff will occur. Once everything that will die has and is decomposed and the water chemistry surrounding is stable again, then it can be considered cured. I would go the slow route in your case, add a few cleaners, and give it 4-6 weeks.

 

Thanks, all. Something I just noticed today. Several of the pieces of live rock have some heavily encrusted areas which started moving. Looking more carefully I noted that these were not areas of live rock, they were bivalves of some sort which were opening. Do these pose a threat to the stability of the system or should I just let 'em ride. Thanks again!- Paul

 

If they live, great! But they may die, which is why you want to give the system time before adding livestock. You want keep an eye on any sponges. They are usually the ones that bite it. Then they turn black and rot--that will kill livestock. In fact, I suggested adding a few cleaners now but I wouldn't even do that yet. Sorry if that was bad advice before.

 

Thanks!- Paul