Would it be permissible for me to add some potassium nitrate to a freshly set up tank (with deep sand bed/live rock) to get the anaerobic bacteria going at the same time as the nitrification bacteria rather than waiting around for nitrates to appear on their own? Wouldn't this speed things up considerably? Then, obviously, a big water change before adding stock.
Question on cycling
- Thread starter Carissa
- Start date
Not sure about it actually speeding things up. I suppose it would benefit them, however, to have an immediate source of oxidized nitrogen to begin reducing. I don't see where it would hurt to add a little, but it is unnecessary.
Please remember nothing good happens fast in SW or FW even, let your tank go thru its cycle without rushing it and it will be in better shape
It would seem to me that it would go faster since instead of having to wait for the ammonia to change to nitrite and nitrate before the anaerobic bacteria starts multiplying, two colonies of bacteria could start growing simultaneously, the ammonia/nitrite and the nitrate/nitrogen gas.
You can try it, but I just don't think, given how slowly they grow to begin with, if adding an oxidized nitrogen source will even be significant during that relatively short amount of time. It would take days and longer for it to even permeate the areas of anaerobic activity, especially with fresh live rock. Once it settles and more animals are present, that time would decrease, due to the turgor created by fauna.
It is up to you, but I just don't think you'll really gain that much of an advantage.
It is up to you, but I just don't think you'll really gain that much of an advantage.
I tend to agree with Amphiprion. I have set up many tanks, I have tried to fast cycle a tank, cured live rock, seeded base rock and mail order live rock and by far the best looking tanks are the ones that were aloud to cycle for 8-12 weeks before adding any fish into the system and then just adding 1 at a time then wait 1-2 weeks before the next addition. The ones that went the 8-12 weeks never ended up with a hair algea or cyno out break and had very good coraline algea growing in a short time, now we also didnt put any lighting on these tanks for about 6 weeks. The tanks I tried to rush thru the cycle had rather large hair algea and cyno out breaks
Well, I guess we'll see what happens. I won't have fresh live rock, I'll mostly have dead reef rock that will have to be seeded with some live rock. I just figured, I could cut off part of the 4 weeks or so that it will take before nitrate starts showing up in the tank. I'm not trying to rush it - just trying to be efficient. 
Since I've never cycled a saltwater tank before, I'm not sure how long we're talking to complete this final part of the cycle to nitrogen gas, and if I can have it very well along before adding fish, so much the better.
As far as algae goes - I know in freshwater, cyano tends to grow in low nitrate systems. Not sure if it's the same thing in saltwater. Also, algae in general tends to grow in the presence of ammonia. I would think this would be the same in saltwater too. So my plan is to avoid all lighting for the first couple of weeks or so until ammonia levels are under control. I'm also not going to add a large amount of ammonia - 0.5ppm or so and that's it. I don't see why people dump large amounts of ammonia into their tank to cycle it, it doesn't cycle any faster and certainly doesn't imitate the presence of fish since fish provide a constant low level of ammonia.
Since I've never cycled a saltwater tank before, I'm not sure how long we're talking to complete this final part of the cycle to nitrogen gas, and if I can have it very well along before adding fish, so much the better.As far as algae goes - I know in freshwater, cyano tends to grow in low nitrate systems. Not sure if it's the same thing in saltwater. Also, algae in general tends to grow in the presence of ammonia. I would think this would be the same in saltwater too. So my plan is to avoid all lighting for the first couple of weeks or so until ammonia levels are under control. I'm also not going to add a large amount of ammonia - 0.5ppm or so and that's it. I don't see why people dump large amounts of ammonia into their tank to cycle it, it doesn't cycle any faster and certainly doesn't imitate the presence of fish since fish provide a constant low level of ammonia.
Ammonia is certainly more efficient for the algae to use, but they are resilient, scouring little organisms. Unfortunately, in seawater systems, nitrogen is normally lacking anyway, so cyanobacteria tends to show up more so with a phosphorus source. Just let the cycle run its course--you'll get there. There are numerous other processes occurring that take much longer and aren't well understood, as well. Another good reason to let it run on its own. Making certain processes more efficient can lull you into a false sense of security that way.
The amount of ammonia/nitrite/nitrogen a tank is capable of processing is directly related to the number of bacteria present (obvuious I know but stick with me on this, I'm going somewhere I promise). Similarly the maximum bacteria population a tank can support is directly related to the amount of surface area available for them to colonise, hence the lbs per gallon reccomendation for live rock. If you add an oxidised Nitrogen source to start producing nitrate/nitrogen fixing bacteria early then these bacteria will reach max. pop. size before the ammonia/nitrite converting bacteria have begun to produce nitrates therefore there will be an excess of oxidised nitrogen and all you'll end up with is increased nitrate levels that will take longer for the anaerobic bacteria to convert. Just my twopennies worth.
Matt.
Matt.