Nano tank cycle

[RickvD]

Hello everyone,

 

A few years ago I was planning to start my first saltwater tank, but life got in the way etc etc.

Now I finally have my waterbox Peninsula 15 tank with all the equipment.

 

I'm close to filling it, however I'm going on vacation to another country in a few weeks. I was wondering if it would be possible to start the cycle +- a week before I go, so the cycle will be done when I get back. As I'm not the most patient person, waiting for the cycle would drive me crazy and this seems like the perfect solution.

[Tired]

Yep, that works fine. Are you planning on bottled bacteria, LFS bin live rock, or ocean live rock? Either way, you can add your bacteria source, sprinkle in a bit of food, and let it alone for awhile, and it should sort itself out.

[RickvD]

3 hours ago, Tired said:

Yep, that works fine. Are you planning on bottled bacteria, LFS bin live rock, or ocean live rock? Either way, you can add your bacteria source, sprinkle in a bit of food, and let it alone for awhile, and it should sort itself out.

I'm not sure yet. Cycling is one of the only things I can't seem to fully understand what the best way is. Bottled bacteria seems like the safest way to go as that is what I've always used on fresh water. Will I need someone to throw some food in every now and then to make sure the bacteria don't die?

[Tired]

There is no one best way, is the problem. Probably the most reliable is to get some decently mature live rock containing algae and various bacteria from a bin at your LFS, but that requires your LFS to sell such a thing in the first place. Ocean live rock is the best way to get maturity fast, it pretty much lets you skip the ugly stage, and it comes with all sorts of fun creatures, but it may bring in pests. Dry rock and bottled bacteria is a slow route to maturity, comes without the useful detritivores, and frequently has a whopper of an ugly stage, but won't come with crabs and unwanted worms. 

 

How long will you be gone? Beneficial bacteria should be fine for awhile without food. 

[phinatic]

I just cycled mine in 3 weeks with dry rock and dry sand. Put some crabs in there for the first week and fed them pellets to fuel the tank. I pulled them out when ammonia spiked and cranked the temp to 84. Tried some API Quick start in the beginning but it wasn't working. Added Fritz Turbo 900 (15 days in) and It cycled ammonia in 2 days. Nitrite took a week from there. I also dosed a small amount of NeoPhos to fuel the bacterial growth. Finished with a big water change to get the nitrates and phosphates back out of the tank. Bacteria are on the substrate, not in the water.

 

- 84 degrees

- 1/4 dose of NeoPhos

- 5x dose of Fritz Turbo 900

- 95% water change

 

[Tired]

Nitrite is so non-toxic in a saltwater environment that it's really not a concern- if the tank is handing ammonia, it's ready for life. And, yes, creature-in cycling is generally not a good idea- not especially humane. You can just add food directly, it'll decay. 

[phinatic]

2 hours ago, Tired said:

creature-in cycling is generally not a good idea- not especially humane

That's why I pulled them after I got them to initially dirty up the tank. Just needed them to make a mess

[Tired]

But that exposes them to ammonia, and involves moving them twice, which is stressful. It also doesn't really accomplish much that wouldn't be accomplished by putting some food in, sans crabs. 

[phinatic]

20 minutes ago, Tired said:

involves moving them twice

Same batch of water and same temp.

20 minutes ago, Tired said:

putting some food in

Food takes time to decay. Crabs it eat it and convert it into waste quickly. Different bacteria breakdown food vs process waste.

[Tired]

Same water, different surroundings, and being caught twice. Not ideal at all. 

[mcarroll]

On 4/26/2023 at 2:04 PM, RickvD said:

I'm not sure yet. Cycling is one of the only things I can't seem to fully understand what the best way is. Bottled bacteria seems like the safest way to go as that is what I've always used on fresh water. Will I need someone to throw some food in every now and then to make sure the bacteria don't die?

"Best" is a relative term.  What makes one method "best"?  Speed?  You will get different answers from different people and different situations.

 

My favorite answer is:  "Best" is the method that completely prevents the ammonia spike.

 

Ammonia spikes are completely unnecessary to the cycle and are the ONLY thing that makes the process potentially dangerous.  Even with all the usual rationalizations, I don't quite understand why we create ammonia spikes at all.  Even in a compressed timeline (eg an emergency move) there are ways to completely avoid having a spike. 

 

In the 1970's I could understand tolerating ammonia spikes to an extent because books were rare or whatever.  But in 2023?  It seems archaic.

 

1. Stock the tank slowly enough, with the smallest critters first and in small numbers (maybe singles), and with at least a week between additions.  
2. There will be no spike....therefore no danger.

 

Also, to know if you have a worrisome amount of toxic ammonia, you need to convert the number for "total ammonia" from our test kits (aka NH4, which isn't necessarily very toxic) into "toxic ammonia" (aka NH3, or un-ionized ammonia).  

 

We do this using a conversion chart that accounts for (at least) tank temperature and pH.  Google it!  🙂  Look for something in black and white so it's old and scientific vs something someone made up for the web.  You should find lots of examples.  API has one on their blog for example...sourced from a journal dated 1970.  (Note:  Their guidance outside the table is generally good, but does not account for marine fish, which process ammonia differently.)

 

As an example of how to use the table....

 

Say your test kit reads 0.30 ppm of ammonia.  

 

If we assume typical values for pH and temperature...say 7.8 pH and 78ºF....the table on the API post gives a conversion factor around 0.035.  

 

0.30 ppm x 0.035 = 0.0105 ppm of toxic (NH3) ammonia.  

 

Still a sign things aren't quite right in the tank (still-developing bacterial population?  something else?), but this is well below the sensitivity of almost all fish, and probably most other critters too.   >0.05 ppm NH3 is the rule of thumb.  (If you're running a hatchery, you'll have lower tolerances in most cases.)

 

You may have deduced that using water changes to combat ammonia could cause a problem, since the tank's pH usually spikes (a little or a lot) when the new water goes in.  Folks obsessing over keeping their pH high would also be in bigger trouble.

 

Any rise in pH "maximizes the toxicity" of any ammonia present.    

 

If we simulate a water change with our numbers above and take the pH to 8.1 and temperature down to 76ºF....the NH3 jumps to 0.06 ppm.  

 

Same 0.30 ppm of NH4, or total ammonia....but now significant levels of toxic ammonia.  

 

Not quite 100% accurate since we don't account for the ammonia removed by the water change, but the point is about how much difference the change in temp and pH makes.  

 

BTW, if you didn't use cooler water in the water change like we did, dropping the tank temperature by -2ºF, the toxic level after the water change would be even higher, around 0.08 ppm NH3.

 

An "instant bacteria" like Bio Spira or Dr Tims (or, ...) would be an ideal solution in most cases.

 

Depending on the overall scenario, a 100% water change would be a valid option that avoids the pH/temp conversion by eliminating the excess ammonia completely.

 

Sustainable Aquatics' White Paper on fish acclimation handles the topic of ammonia really well:  http://www.sustainableaquatics.com/docs/Acclimation-White-Paper.docx

 

I would also suggest looking at these excellent articles on the subject by @seabass:

• A Look at Ammonia
• A Guide to Reef Aquarium Cycling

 

[phinatic]

8 minutes ago, mcarroll said:

Ammonia spikes are completely unnecessary to the cycle and are the ONLY thing that makes the process potentially dangerous.

Great point. Spike is relative. When I mentioned having a couple hermits in a dry rock tank, the total ammonia was small, and due to the low pH at the time, the toxic component was also small. I would also note that I turned the temp up to 84 after the hermits were removed. Same goes for pH. That was also increased afterward.