Jump to content

Cycling help


Recommended Posts

I'm a bit of a novice so looking for some guidance. I've had my 36 gallon for just over a month now. Initially added some water sprite and Christmas moss and a whole bottle of Fritz zyme. Running an aquaclear 50 filter with intake sponge.

Initially Ammonia jumped to 1ppm and nitrites got to about .5ppm. After about a week ammonia dropped to .25ppm and nitries to 0ppm so we added our school of 13 neon tetras. Ammonia stayed at .25ppm with nitrites still at 0ppm so we added our Honey Gourami and 6 emerald Corys. Same readings so we added our 2 zebra Loaches, adult bristle nose Pleco and a baby koi angel. Ammonia has now floated between .5ppm and 1ppm. 

I'm doing larger water changes (30-40%) every couple days and treating the water with prime and everyone in the tank is doing fine, however the ammonia is still not dropping.  I'm definitely not over feeding and am only feeding 6 days a week. Nitrates are consistently around 10ppm and the plants are thriving and we've recently had a brown algae bloom. I just added some extra bio media to the filter 2 days ago since there was room in there. I had ammonia pads in there but that didn't seem to help. Am I just being impatient here?  Shouldn't my ammonia levels be dropping? They've never surpassed 1ppm and based on using an ammonia calculator my free ammonia level should be safe for the fish but I'm still treating with Prime out of an abundance of caution. I just tested again this morning and got 1ppm so gonna do another large water change. I realize I probably jumped the gun a bit on adding fish but the bottom of the tank is definitely clear of detritus with all the water changes I'm doing and like I said I am sure I am not over feeding. Do I just need to allow more time for the cycle to complete?

Link to comment
Share on other sites

Yeah I missed that you posted this.   What is the nitrate level?  If no nitrates then the tank has probably not fully cycled.

Think of the cycle in phases.

Phase 1:  Ammonia levels rise.

Phase 2: Nitrites rise and ammonia starts to drop.

Phase 3: Nitrates start to rise, nitrites begin to drop, ammonia near zero.

Complete: Nitrates stable, nitrites and ammonia near zero.

Of course this is over-simplified and varies based on a bunch of factors like filtering, bio-load, plants, over feeding, lighting...


Maybe back off on the prime a bit?


Edited by KBOzzie59
I missed the nitrate level you posted
Link to comment
Share on other sites

I've been getting consistent Nitrate readings of around 10ppm. I'll back off on treating and see how it goes. I work from home and with Covid don't really go anywhere anyway so I'll just keep a close eye on the fish. As I said they show zero signs of ammonia poisoning and everyone is super healthy and active. Appreciate the insight

Link to comment
Share on other sites

What are the pH and KH in your tank?  I'm guessing the pH is not super high, based on your ammonia chart comment, but you should also note that if it drops too far below 7.0, the bacterial colony may have a harder time getting established.

I recently went through a fish-in cycle (albeit in a smaller tank with waaay fewer fish).  I took pretty much the exact same approach as you are taking for the ammonia spike- water changes to keep it under 1.0 ppm and dose with prime to be safe.  I got through it with no problems at all, just needed to be patient.

The nitrite spike is a completely different story though- as it is highly toxic even at low levels.  I luckily didn't lose any fish, but my livebearers spent an entire week barely moving at the top of the tank, even while I was doing everything I could to keep nitrites under 0.5 ppm.  I worry that with all those fish, you're going to have to do multiple water changes daily to keep things under control....


Link to comment
Share on other sites

@MyDaughtersTank  I have the same understanding as you that is, nitrite is toxic at low levels. But on both the tank above and this aquarium (Nerm)

there was quite a bit of nitrite for a week and yet the angelfish and guppies in both aquariums were completely unfazed, happy, cavorting, chasing, and eating like pigs the entire time.
And no water changes during this time period. I also have other data from other devices that measure ammonia using a different protocol that leads me to believe the graphs above represent some level of reality.
Nerm is a tank with black sand capping an inch or two of dirt. EcoComplete above has an EcoComplete substrate. I am not sure what to make of the various outcomes yet.
Link to comment
Share on other sites

My PH has been steady at about 7.8. I do have some crushed coral mixed in with my imagitarium black sand. I measured GH and KH about a week ago. GH was 6 and KH was 4. According to the reading that is between 50-100ppm for both which is right in line with where I want to be at least according to the API instruction sheet.  I have been testing nitrites every other day but it has been at zero since about day three of the tank being started. 

Link to comment
Share on other sites

11 hours ago, tolstoy21 said:

@DanielAre those nice graphs a result of the journaling in a spreadsheet your were talking about in an earlier thread a while back?

I have the attention span of a flea. I have tried writing things in the journal but I am totally inconsistent.

But I do like to take pictures so that has become my new form of keeping records. Those graphs above are derived from a time series of test results like this:


I put notes on the photos and then later can make graphs of the data. The way I figure it, a picture is worth at least a couple dozen words.

Also the process of making a time series and a graph forces me to pay attention and observe and record details. Eventually when I collate and organize the data I begin to see patterns that were not evident to me in real time. Memory is fluid and rife with bias and is a poor substitute for data collected systematically.

And later when the fog in my head begins to clear and I learn something I get a dopamine rush! As Democritus once said, 'I would rather discover one true cause than gain the kingdom of Persia'.

  • Like 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...