Conservative cycling

Shilpan

Member
Hello
Newbie here setting up a 400L tank. Getting ready to cycle with dead rock and dead sand, but I had a question. I was doing some research and indeed I found many posts where people had sky high nitrates (>160ppm) post cycling. Often requiring a 100% water change following the cycle, or multiples 50% changes because obviously it takes a long time for bacteria which produce N2(g) to form deep within the rock and maybe then not enough.

It seemed to happen because people either chucked all their dead rock in, or kept habitually dosing ammonium chloride to feed the bacteria. Lots of nitrates thus produced.

So why not just "cure" the rocks in RODI water for a week to let things die off so they're really clean (saving salt here). Then start cycling in salt water. And ghost feed extremely sparingly so you only get an ammonia spike of say 0.25? Thus less nitrates, and I save $150 worth of salt for a 100% water change and the saltwater used to cure .

If I add only 2 clowns to start, surely that's enough ammonia converting bacteria to support them? Or do I risk an ammonia spike when adding fish?

Apologies if I'm being stupid in trying to save money, but thought I would check if this is safe.

Thanks
 

deejeff0442

Active Member
All comes down to patience. Time and more time. I have cycled alot of tanks . Takes 6 to 8 weeks. If you are in a big hurry this isn't your sport. I have never done a water change during or a month after the cycle did itsome thing
 

2quills

Well-Known Member
There's general 2 types of bacteria. Nitrifying (breaks down ammonia) and denitrifying (breaks down nitrite and eventually nitrate).

The later takes more time to develop and catch up which is why most tanks go through algae break outs right after the first cycle. They typically level off after time with good husbandry. Otherwise, in most cases people have to rely on other means like scrubbers, water changes etc.
 

bang guy

Moderator
I believe I already sent you a link to my cycle method. Part of that includes just enough water changes to keep ammonia below 0.5.

I've never worried about Nitrite. I wouldn't even bother testing for it.
 

florida joe

Well-Known Member
Not sure if Bang means nitrates instead of nitrites. This is my take on you starting a new tank. TAKE YOU TIME. It’s easier said than done for new hobbyists and seasoned ones as well believe me I know. You start the nitrification and de nitrification cycle which is the corner stone of what allows up to maintain a closed saltwater aquarium system. In your case you are using the die off from the rocks you introduce. This ammonia starts the cycle of nitrification. The amount of die off predicates the amount of bacteria colony’s turning ammonia into nitrites. The nitrites are then food for bacteria to consume the nitrites and we are left with nitrates. Now starts the di nitrification. The nitrates are fuel for the growth of anaerobic bacteria with in our rocks. The more nitrates the more colonization of anaerobic bacteria. At this point our tanks are trying to find equilibrium. As more fuel is introduced into our tank the more colonization the less fuel there is a die off of nitrifying and de nitrifying bacteria. As In your case and all tanks everyone's is different if you were to have an off the chart nitrate reading don’t rush to add fish let the tank find its balance. Ghost feed just enough to keep your cycle going as far as nitrification let the anaerobic bacteria catch up to your nitrates. When your nitrates are within what you are comfortable with then increase your ghost feeding to what you will be feeding your clown fish. Run some tests and if all is normal add the fish.
 
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Shilpan

Member
Thanks guys! So you advocate just allowing the nitrates to go wherever they go and then waiting for them to actually come down via denitrification to 'safe' levels before fish. And that as long as I wait they will come down. Read a lot about people saying their nitrates didn't come down post cycling. But I guess that just means they didn't continue ghost feeding and waiting long enough. Awesome I'm in no rush, I'll wait months if I have to, till nitrate comes down.

Sorry Bang guy I didn't read that link!! I'll go read it now :)

Just making water (oh My the RODI unit takes ages) then I'll start this baby off!
 

florida joe

Well-Known Member
Bang I am going to have to respectfully disagree on your message here. Nitrites and I believe you would have to agree are right behind ammonia for toxicity in our tanks. Don’t know how that is considered mostly harmless. If that was the case however we could introduce fish into a newly cycled tank right after no ammonia is detected.
Bang I think the problem here is we are talking about two different situations an established tank and a newly set up tank. I no longer test for nitrites as my tank has been up and running for many years BUT the op is setting up a new tank. IMO he should be testing for nitrites just to get a feel for how his tank is progressing
 
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Shilpan

Member
1) Sorry Bang I can't find the link :( I jus checked all my posts.

2) @florida joe, I came across some readings which suggested nitrite is only really harmful in concentrations above 100-200ppm, maybe even 300ppm. In your experience is this not the case?

(And yeah I have a nitrite test kit so I'll be doing it anyway, helps me track cycling).

3) what's safe nitrate level for fowlr? How about softie tank?
 

bang guy

Moderator
Joe my good friend, it's nearly impossible to obtain a lethal level of Nitrite in a saltwater tank. This is a myth brought over from freshwater systems where Nitrite is indeed a deadly toxin. The ion exchange in fish gills just doesn't happen in saltwater. In fact, perhaps Shilpan can tell me if I'm wrong, I believe the cure for Nitrite in a freshwater tank is to add a little salt.
 

beaslbob

Well-Known Member
IMHO if you start the tank with an algae turf scrubber (ats) or macro algae (usually in a refugium) it is possible to cycle the tank with no measureable ammonia spikes. Because the algae will consume the ammonia before nitrates. So at first, you can get a minor (20ppm or so) nitrate spike. Which will come down as bacteria build up and consume the ammonia. The algae will then be force to use nitrates for nitrogen.
With algae you don't worry about sky high nitrates and 100% water changes and so on.
 

bang guy

Moderator
3) what's safe nitrate level for fowlr? How about softie tank?
IMO it should be kept below 50ppm in a FOWLR, closer to 10 is better.

Softies do appreciate some Nitrate in the water, still below 50ppm and closer to 10 is better.

Below 10ppm for any hard corals and closer to 1ppm is better.
 

Shilpan

Member
Thanks bang guy for the link and the ranges.

Yeah you can add a tiny bit of salt. That's because chloride ions in the salt will compete for nitrite exchange in the fishes gills. Since marine fish are surrounded by chloride ions they're less susceptible to nitrite.

Well, to be clear, I know my freshwater fish are much more susceptible to nitrite because of the lack of saltwater. I don't know much about marine fish.
 

Shilpan

Member
Hey bang, so you keep ammonia under 0.5ppm.

Is that only to keep live rock alive? Or to prevent crazy high nitrate levels post cycle?

(I ask because I'm only adding live rock (like fresh from my LFS's tank this no die off) near the cycle end so no ammonia killing my organisms to worry about). I'm cycling with decomposition from dead dry rock. Will ghost feed once ammonia goes away.
 

bang guy

Moderator
I try to keep the ammonia low and steady for the rock infauna and it creates a stable system much faster than with high ammonia levels. With dead rock and sand I agree you have no worry.
 

bang guy

Moderator
I probably created a misunderstanding here. It's toxic sure, but I doubt anyone could accidently have a Nitrite concentration so high it endangers marine fish. In my experience 1.0ppm would be a high Nitrite level. I don't think I've ever seen 2.0ppm but I'm sure a few hobbyists have managed it with the super high ammonia method of cycling. To get it to toxic levels I would think you would have to purposely add Nitrite to the system.

^ edit - I can see a case where a super overloaded holding tank might get Nitrite to 5ppm or more. Do Nitrite tests even go that high? I don't have a test kit to look at.
 
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florida joe

Well-Known Member
Well we all agree nitrites are toxic. Now I’m new to the hobby I have a 29 gallon tank. I over load it with rock to start a cycle and for good measure i add a shrimp.. My ammonia is off the chart. Now it’s zero I check nitrates zero wow I am ready to go. I have no need to test nitrites. So in go my fish BUT wait they are dying how that can be. Seems maybe I should have checked my nitrites. I did not have an accidental toxic level of nitrites it was the result of a newbie mistake. nitrite test kits go up to 5 ppm.
IMO when it comes to our livestock there is nothing wrong with going the extra mile to assure even if it’s a million to one chance that I will not put them in jeopardy. Better test then be sorry
 
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