As mentioned a couple times already in this thread, with nitrite present, nitrate readings are falsely inflated.
Cycles do not get stuck.I started cycling my 57g tank on 8/27 (19 days ago) with Brightwell Microbacter quick start and start XLM. I used dry rinsed sand and cured/dried marco rocks (curing was probably overkill but I wanted to make sure there were little to no phosphates. After soaking in RODI water for a few days, phosphate was .02.I let the rocks dry and spent the next month building the aquascape. Ammonia measured 2ppm on day 1 and gradually dropped to 0ppm on day 9. Nitrite gradually increased to 2-5ppm by day 9 where it reached it's peak and appears to have been stuck there ever since. So nitrite has been at least 2ppm for 10 days. I have 2 test kits for nitrite/ammonia - RedSea and API. RedSea only measures Nitrite up to 1ppm and I measured well beyond 1ppm since 9/3. With API it's very difficult to tell a difference between 2ppm and 5ppm, but I believe it's been somewhere between 2 and 5ppm.
Microbacter claims a typical cycle using this method is about 7 days.
On 9/8 (day 11) I added about 20 MarinePure Ceramic Biomedia 1 1/2 Spheres that were in the sump of my 20g established tank for a couple months to the sump of the new tank with hopes of adding some beneficial bacteria since I had used all of the Start XLM.
Per Brightewell's instructions:
"Although product can withstand elevated temperatures for short periods of time (a few days), for best longevity and highest potency, keep below 80°F and if possible, it will be best kept refrigerated at 50°F to much prolong shelf life."
For 1 month I stored the Start XLM around 68 degrees. Not sure who keeps their fridge at 50 degrees so that wasn't much of a feasible option for me, so I figured storing it in the basement which stays below 70 degrees with the AC on in the summer was the best option. Sounds like this is within reason although perhaps not optimal to prolong the life of the bacteria.
Is the cycle stuck? Should I do a water change? Leave it alone? Here are the most recent test results (ammonia is zero with both test kits).
I don't think it's as simple as dosing ammonia, nitrate and expecting bacteria to successfully colonize every tank. If that were the case, every person who tried this method would be successful, which obviously doesn't work out that way as indicated by this comment thread. I think there's more to it than that.
As I see it, if the tank clouds up and clears up, it's cycled. End of discussion and I don't care what our resident "scientific community" thinks needs to be satisfied here. If it's done, it's done. The thing is, I don't know if OP's tank ever clouded up during the process, indicating a bacterial bloom, which is what I personally look for in a successfully cycled tank... out of probably a few dozen successful tanks I've started. If this wasn't ever the case with this tank, for peace of mind, by all means, throw some food in and cause another bacterial bloom. There's no livestock at stake here and within a week or two, the tank will be good to go FOR SURE anyways.
That is true. @Lasse convinced me to get Tropic Marin nitrite/nitrates test that allows one to test both and estimate how much “nitrite” is present that is measured as nitrate in the test method because these molecules are confounding in the simple test kit. My test for nitrates can show that it is present when actually nitrates are zero and the nitrite is fogging up the test results. That is correct.
www.reef2reef.com
This was the cloudiest the tank got throughout the last 20 days. Picture taken 12 hours after adding ammonia and start XLM.
From Brightwell: "Pitfalls: There are several reasons why hobbyists do not achieve a fast 7 day (approximately) cycle with this product. These are all controllable if careful attention is paid. Even when these factors are present, the tank will still cycle, it will just take more time. 1) Failure to dechlorinate properly. Always use Brightwell Erāse-Cl to completely remove chloramines and chlorine from tap water. Chloramine and chlorine are lethal to the bacteria in this product and if not removed, will cause it to fail! 2) The overuse of ammonia or using household ammonia! Ammonia is toxic to bacteria, even though they consume it, just like it is to fish and invertebrates, so if you overdose the ammonia, it will kill some of the bacteria and it will take longer to cycle! You will still achieve an excellent and strong cycle, it will just take longer, possibly much longer. Also, if you purchase household ammonia, it may have toxic additives, dyes, surfactants and cleaning agents that will stunt the multiplication of the bacteria in the product. Brightwell recommends that you use MicroBacter QuikCyclTM as directed and test so that you don't overdose! 3) In a brand new aquarium, there can sometimes be surfactants, mold release compounds or oily chemicals that coat brand new glass, acrylic, tubing and pumps. These compounds can negatively affect the cycle. It is therefore recommended that you clean all new parts with a mild soap and water and then RINSE THEM VERY WELL! (Do not use antibacterial soap!) This should remove the compounds that can stunt the multiplication of the new bacteria 4) Brightwell recommends that you not use any other type of bacteria product until your cycle with this product is complete !!! Do not even use MicrōBacter7 or MicrōBacterCLEAN until the cycle is complete (then you will want to use one of them to help through the "ugly stage". (MicrōBacterCLEAN will work best for this.) 5) Do not use live sand and particularly DO NOT USE dry seeded artificial live rock until cycling is complete. There are no dry bacteria species that will be compatible with this nitrifying bacteria product or that are useful to cycle an aquarium at all! To use a dry bacteria will only lengthen the time it takes to cycle by many weeks and increase your work many times! Wet cycled live rock or even previously cycled wet man made rock will work fine (although this may be a bad idea due to the possibility of introducing parasites or pathogens from another aquarium). Dry sand is fine to use, but not bagged, so called "live sand" because the manufacturer will usually introduce other bacteria species to replace the natural bacteria that will die during storage and these will be counterproductive to your cycle. Also, several so called "probiotic" salts are available. Again, there are no species of bacteria that are conducive to cycling that are available in a dry form. Therefore, do not use any salt that is labelled as probiotic or says it contains dry bacteria. Note: What to do if you must use live sand or dry seeded live rock - go ahead and use them with the MicrōBacter Start XLM, just realize the cycle will be impeded. It will take more XLM to seed the system (double the dose if you can) and the cycle will likely take 2 to 4 weeks longer to complete because you are working against the XLM, but when completed, will work just fine. 6) DO NOT USE CARBON IN YOUR FILTER until the aquarium has cycled fully or 30 more days has passed. DO NOT USE PHOSPHATE REMOVERS, FILTER RESINS, GFO or other non-biological filtration media until the aquarium is over 30 days old or then you register phosphates on your test kit over .04 PPM. If you do, you will lengthen the cycle. Bacteria require some phosphate to multiply rapidly! Use XportTM, MicroBacter LatticeTM or other filtration media that needs to be populated with bacteria! These will work well. 7) The addition or dosing too soon of active iodine compounds (such as Lugol's), nitrate removers (such as nopox which is made from poisonous methanol), or other additives that are bacteriacidal. If you are going to add these, It is a good idea to wait 30 days."
The main question here is the actual toxicity of the level of nitrite present in the tank. You can absolutely have a "cycled" tank with some degree of nitrites which is why "fish cycling" tanks actually worked. While I wouldn't start by adding nitrite sensitive creatures first, I would add most fish our hobby sees and WELL before any health issues come up, the normal biological process of that added fish is going to carry the tank through any remaining cycling that it needs. There of course is more maturation that our tanks go through biome-wise over the course of a year. Obviously we don't have to wait that long to add livestock. This is why I go with the "clouding" indicator instead of swishing a beaker in my lab until I see "ideal" parameters. Things don't have to be chemically "ideal" from our input and I don't need a test kit to tell me the conditions for bacterial grow and denitrification are present when the water in the tank, literally in front of me, is undergoing a bacteria bloom. We're only starting the process and IME, nature does a fantastic job of completing the process. We're likely slowing down that process by interfering with it like we're punching in code and expecting instantaneous results.And I’ll add this, 38 pages of actual reef tanks showing no harm no stuck cycles and 100% safe fish carry, nitrite can’t be pinned on anything bad, don’t own the kit
How to unstick any seemingly stuck cycle
Updated Cycling Science in Action This is a testless reef tank cycling thread, the only one from any board. If you ever had trouble with reef tank cycling in the past, you won't any longer after working some jobs with us. chances are you are using/about to use a method of reef tank cycling...
that thread shows your tank will carry fish. It’s good to use actual reef tanks in reef tank cycle studies
if you own a nitrite kit in cycling, expect doubt, confusion, hesitation and steps you have to take to unstick the cycle
and if you don’t ever own the kit, you get those results above
nitrite testing only has bad outcomes, not good ones. It makes reefers lose all focus on fish disease: not once is fish disease discussed in non reef tank links on nitrite, we can see.
fish disease has never been discussed in this thread we are posting in, either- see how false nitrite concerns exclude preps for what really kills fish?
nitrite measurement and reaction is bad for the hobby, vs good. Don’t own a nitrite kit for saltwater reefing.
And as I state!
Now your nitrification process is complete cycled
The entire point of cycling is to keep ammonia down long enough that heterotrophic bacteria can outcompete nitrosomonas for ammonia capture. Nitrosomonas is almost non-existent in mature reef systems, and is dwarfed in ammonia capture by heterotrophic bacteria, corals, coralline, and other reef organisms.
There are no nitrite-sensitive organisms in reef tanks. It literally takes hundreds of ppm to bother shrimp larvae in saltwater, because the reason nitrite bothers fish in fresh water is it's a chlorine antagonist in fish's gills. Marine tanks are literally 19,000ppm chlorine - there's so much chlorine that it doesn't matter.
