Cycle question for experts

[Jekyl]

Was reading along with one of the many cycle posts that pop on on here. Thought came to mind about the use of bottled bacteria and larger tanks. Is it even needed? Say you're starting a 180g tank. Would adding one juvenile or even a par of clowns ever get the ammonia levels to where it would be an issue? Are bottles of bacteria something for smaller tanks only? Interested to know the scientific end of it. I know the @Lasse method doesn't bother with any bacteria. Interested what @Randy Holmes-Farley thinks on the matter. Or if @brandon429 might have seen something documented?

 

[brandon429]

I think it should be tested using digital gear, then if nh3 rises above .05 ppm we can know for sure. Nobody has tested this accurately above to know the answer imo. There will come a time after x days wait where the presence of the fish cycles the substrate in question, will be interesting to know if dilution alone can prevent toxicity before it self cycles.

Lasse once mentioned the fish food is more bioload than the single fish / feed loading really stresses uncycled tanks, they go gray and smelly

 

[Miami Reef]

I personally would at least put a piece of live rock or maybe dose a small bottle of bacteria. Just so I know there’s going to be some nitrifying bacteria population that will reproduce to handle any ammonia.

I think with all dead rocks the tank would need about a month to establish the bacteria. I’d rather just dose a bottle and not worry about testing ammonia (with reasonable stocking of course).

 

[neilldrever]

I have always fishless cycled using bottled bacteria since it came onto the market along with Ammonium drops to bring the tank up to 2ppm which as I understand is the equivalent bioload of a well stocked tank. Then when livestock is added you can be confident that there is ample bacteria to cope with the bioload and any excess will naturally die off until equilibrium is reached.
Adding livestock to a sterile tank with no "live" material such as sand or rock and just leaving it to be propagated by atmospheric nitrifying bacteria usually causes Ammonia spikes while the bacteria colonise the tank but having said that with a large water volume that could be negated. Interested to hear what others think.

 

[Rmckoy]

This is a interesting topic .
I’m no expert but I will offer my 2 cents

with my old 90 gal
I had roughly 100 lbs of rocks in it .
when I transferred everything to the 230 I added the rocks , fish which everything was ok .
I later added the sand which was once said to be beneficial .huge mistake .
but the lesson from this would have been .
the rocks did have sufficient bacteria to support the same bioload but moving the sand doesn’t carry anything good with it .

 

[vetteguy53081]

Using the 660g as an example, I use the same cycle principal as would apply to smaller tanks utilizing denitrifying bacteria along with pohls zeo Bacter a and Zeostart. Its about the tanks ability to break down waste and handle bio-loads in which in my case, I was transferring over 20 fish from a previous 360g.
While larger system will be more forgiving, you want same bacterias to be available tp break down organic waste and fish waste and debris that typically enters the environment.

 

[Jekyl]

My thoughts were at some point the volume of the tank vs small bio load should tip the scales in favor of not needing the bacteria in the first place. Just wondering if there was a way to figure that out. I completely understand the reason behind the current recommendations. However if you're adding 1 fish to a 180g tank, is the bacteria in a bottle just for your piece of mind and not that 1 fish?

Edit: just to clarify, I'm not currently cycling a tank and don't plan on ever using dry rock. Just thought this would be a fun discussion.

 

[Spare time]

My thoughts were at some point the volume of the tank vs small bio load should tip the scales in favor of not needing the bacteria in the first place. Just wondering if there was a way to figure that out. I completely understand the reason behind the current recommendations. However if you're adding 1 fish to a 180g tank, is the bacteria in a bottle just for your piece of mind and not that 1 fish?

Without adding bacteria you are reliant on whatever is arriving with the fish or via aerosols or something from another tank (which can take a while). It's just more ethical to add some with the fish if you do a fish in cycle.

 

[Jekyl]

Without adding bacteria you are reliant on whatever is arriving with the fish or via aerosols or something from another tank (which can take a while). It's just more ethical to add some with the fish if you do a fish in cycle.

I 100% agree of the issue that needs to be prevented. However with just the ammonia supplied by the fish and food the tank will cycle on its own. The question is at what point is adding the bottle of bacteria just not necessary? Plenty of people do a fish in cycle without causing harm to the fish. @Lasse ran fisheries and doesn't use bottled bacteria starting a tank.

 

[Lasse]

@Lasse ran fisheries and doesn't use bottled bacteria starting a tank.

You must have misunderstood me - step 6 in my method

6) Add some nitrifying bacteria every day for three weeks or inoculate with detritus from an already functioning aquarium every day. There are many special bacterial strains available to buy, including a mixture of nitrification and break-down bacteria--avoid them in the beginning--only the nitrifying bacteria are of interest. I normally use a freshwater product--Sera NitriVeck--and dose 20 ml per 100 liters/day. Do you have an old aquarium running? Then take and turn out the filter in a few liters of water--fresh or salt--does not matter. Put it in the refrigerator, and then pour in an appropriate amount every day into your new aquarium. At the start of an aquarium it can be a good method to use an internal foam filter, which helps the nitrification to start. It can later be removed if you want.

Its right - I do not use the mixed bacteria products only those that only contain the nitrifying strains

Sincerely Lasse