Mixed Rock Cycling

[Ryan_E]

Just got my 45 gallon tank setup. It has a sump too. I have 30 pounds of reefcleaners dry rock in there along with somewhere around 30lbs of caribsea dry sand, and I threw in about 6 pounds of cheap live rock (one of the pieces actually has a coral skeleton on it). Will this provide me with enough bacteria to help seed my live rock? I have not added an ammonia source yet. The tank has been cycling for four days. I haven't decided on what source of ammonia to add. I searched around, but did not find any other threads that had the exact situation as me. Thanks!

[seabass]

When using live rock, I normally don't recommend adding additional ammonia (as it could kill some of the beneficial life on the live rock). What I normally recommend is to prep the dry rock separately and adding ammonia just to the dry rock. After it's prepped, then I'd add the live rock.

 

Given what you have now, I'd probably just let it cycle as is (not adding ammonia). Once ammonia has been undetectable for over a week, I'd slooowly add livestock (starting with a small cleanup crew).

[Ryan_E]

When using live rock, I normally don't recommend adding additional ammonia (as it could kill some of the beneficial life on the live rock). What I normally recommend is to prep the dry rock separately and adding ammonia just to the dry rock. After it's prepped, then I'd add the live rock.

 

Given what you have now, I'd probably just let it cycle as is (not adding ammonia). Once ammonia has been undetectable for over a week, I'd slooowly add livestock (starting with a small cleanup crew).

Thanks seabass. I thought so too, but I got to reading and overthinking. So you think that I can just leave everything as is and not add anything (no shrimp, no food, no pure ammonia)? I ran an ammonia test yesterday and the test came out to be a color somewhere between 0 and 0.25 ppm. Probably closer to 0. I know it will take quite some time before I detect any nitrite or nitrate so I didn't bother doing either test.

[seabass]

Once ammonia has become undetectable for over a week straight, the cycle will have become established. Granted, you only started with 6lbs of live rock (something more suitable for a 10 gallon tank). Therefore, I'd stock the tank like I would a 10 gallon tank. Once you start adding livestock, you'll be introducing an ammonia source, so the bio-filter will adjust accordingly. Instead of adding ammonia, I'd consider dosing bacteria just before you add your first fish.

[gus6464]

Go to an LFS and get a bottle of microbacter 7. Come home and dump half the bottle into the tank. Then keep dosing daily until bottle is gone for a week. Profit.

[Ryan_E]

Go to an LFS and get a bottle of microbacter 7. Come home and dump half the bottle into the tank. Then keep dosing daily until bottle is gone for a week. Profit.

Now? or just before livestock like seabass said?

[gus6464]

Now? or just before livestock like seabass said?

 

Now to speed up the bacteria spreading process. I have cycled a 50g tank with a little tiny bit of live rock and a bottle of MB7 in 2 weeks. Then added SPS in week 3. No problems.

[seabass]

I have relied on DrTim's One and Only when starting up new tanks and prepping dry rock. The thing about dosing bacteria is that it needs ammonia to thrive. This was why I recommended waiting until you were ready to add a fish (an ammonia source).

 

The live rock is also an ammonia source, so it will also provide ammonia to the new bacteria. Adding it right away wouldn't necessarily be wrong. You'll find that there are always a number of ways to accomplish the same goal.

[Ryan_E]

I have relied on DrTim's One and Only when starting up new tanks and prepping dry rock. The thing about dosing bacteria is that it needs ammonia to thrive. This was why I recommended waiting until you were ready to add a fish (an ammonia source).

 

The live rock is also an ammonia source, so it will also provide ammonia to the new bacteria. Adding it right away wouldn't necessarily be wrong. You'll find that there are always a number of ways to accomplish the same goal.

Exactly why I am confused haha. Very small amount of live rock has dead stuff and bacteria on it. Dead stuff and LR creates ammonia. Bacteria uses ammonia to thrive. With this small amount of live rock, will it produce a large enough ammonia spike, and if it does, will there be bacteria remaining to break it down and spread.

[seabass]

A large ammonia spike is not a requirement. You could start a tank with fully cured live rock and never experience an ammonia spike at all. When the bio-load exceeds the capacity of the bacteria to process ammonia, you'll witness an ammonia spike.

 

Nitrifying bacteria just breaks down the ammonia into nitrite, and nitrite into nitrate. As long as there is an ammonia source, the nitrifying bacteria will adjust to the current bio-load.

[Ryan_E]

A large ammonia spike is not a requirement. You could start a tank with fully cured live rock and never experience an ammonia spike at all. When the bio-load exceeds the capacity of the bacteria to process ammonia, you'll witness an ammonia spike.

 

Nitrifying bacteria just breaks down the ammonia into nitrite, and nitrite into nitrate. As long as there is an ammonia source, the nitrifying bacteria will adjust to the current bio-load.

Got it. So correct me if I am wrong here. Currently, I have a small amount of live rock. This means that I probably also have a small amount of nitrifying bacteria and ammonia source. So when I test, I may or may not detect high ammonia in my tank due to the ratio of high water volume to low amount of LR. If I do detect ammonia, I will let the cycle run its course and wait until I cannot detect ammonia, or nitrite. Then I may or may not be able to detect high nitrates (again due to that ratio). Once this happens, I am cycled, but since I started with such a small amount of bacteria, I need to stock my tank as if it were a smaller tank and let the bacteria adjust to the new bioload. With this small amount of LR, what type of cycle should I expect? Very low ammonia, nitrite, and nitrate readings?

[seabass]

That's essentially correct. I usually don't test nitrite as it's not very toxic in a marine environment, but it will tell you about the cycle. Since you have some detectable ammonia, I'd expect that some nitrate will show up as well.

 

Eventually the dry rock will support as much bacteria as live rock would have. If you add livestock slowly, your tank will continue to adjust to the new bio-load (until you are fully stocked).

[Ryan_E]

That's essentially correct. I usually don't test nitrite as it's not very toxic in a marine environment, but it will tell you about the cycle. Since you have some detectable ammonia, I'd expect that some nitrate will show up as well.

 

Eventually the dry rock will support as much bacteria as live rock would have. If you add livestock slowly, your tank will continue to adjust to the new bio-load (until you are fully stocked).

Alright, thanks Seabass. In your experience, how long do you think a cycle in my situation would take? Should I plan on testing daily since I most likely will have lower readings? My plan is to add livestock slowly. One fish every 2-3 weeks and I may dose some bacteria with the first fish just to play it safe. Thanks for all of the clarification. I needed a sanity check! ha.

[seabass]

It's almost impossible to predict how long it will take before the ammonia spike is over. However, being four days in and ammonia hovering around 0.25ppm, I wouldn't expect it to take that much longer (maybe a week or two). I'd probably test every two or three days just to see how things are progressing.

[Ryan_E]

It's almost impossible to predict how long it will take before the ammonia spike is over. However, being four days in and ammonia hovering around 0.25ppm, I wouldn't expect it to take that much longer (maybe a week or two). I'd probably test every two or three days just to see how things are progressing.

Awesome. That is exactly what I have been doing. Thanks again. I think I will start a thread for my tank soon!

[piano15]

I just wanted to say thanks to seabass, the info you provided was great!