Cycling Questions (Week 2, Waterbox 20 Cube)

[lrosenberg5]

Hey All - Have some cycling questions. I have a Waterbox 20 cube setup and have been cycling for almost two weeks.

For some background, I am using CaribSea live sand (used good amount of liquid from bag), dry rock and Imagitarium pre-mixed saltwater (will phase this out once I get RODI filter). Used Dr. Tims and dosed ammonia on day 1 and on day 4. On day 4, I dosed 25% of recommended given my Ammonia was still at 2ppm. Also worth noting, I got my tank secondhand (from @reefer_nyc) and there was definitely some dried (probably) organic matter on the tank when I filled it. Recognize I should have properly cleaned it better but I was impatient and doing everything in a tiny apartment. I have been topping off the tank with distilled water a few times a day and the tank has been at 80-81 degrees F.

See my testing chart below. Using the API test kit which has been easy to read so far. Only thing is that the Nitrite reading is a deep purple that doesn't really match the chart so I assumed it's been at 5ppm.

Given Nitrates are now maxing out the test kit (160+), do I do a water change, re-dose ammonia now that it's low again, or hang tight? Appreciate any advice you all have!

 

[brandon429]

your cycle is done, nitrite no longer factors in updated cycling science. it was a big deal in the old rules, but its chemically neutral is why nobody minds it anymore.

its only about ammonia control, and you've met the timeframe on the bottle bac directions as well. you are done cycling and can add fish, your test kits are subject to misreads in all cases.

your issue is fish disease, not nh3 lack of control. one of the benefits of using updated cycling science vs old is we're tracking what matters and what can limit fish loading.

 

[TexanCanuck]

Hi there ... nice looking tank!

While I agree with @brandon429 that it appears your cycle has finished, and that Nitrites (NO2) are definitely not a problem at that concentration, it would be a good idea to periodically test your nitrites once every few weeks for a couple of months to make sure they come back down. My thinking here is that the nitrifying bacteria culture you are trying to grow should also be capable of processing nitrite (NO2) into nitrate (NO3) ... so even though NO2 isn't a problem for your fish, watching this happen will give you more peace-of-mind that you have a robust biofilter.

In the meantime, a large water change would be in order to bring down your nitrates and you should be good to start adding fish.

At the risk of preaching to the choir, just make sure you go slow when adding your livestock ... don't add everything at once. While you have a functioning biofilter now, it is still quite limited in capacity and you can easily overwhelm it if you add too much livestock all at once. Add a few fish, let the biofilter mature a little more, then a couple of week later add some more fish, etc ... you get the idea.