Confused about cycling my tank

[Alexervin239]

So my 17g cube has been running now for about 2 weeks. It has 10lb of live sand and 15lb of BRS pukani dry rock. I let it run without adding anything for about a week. Then I added about a teaspoon of fish food for 2 days and added stability as directed on the bottle. I knew the cycle wouldn't be complete but my test kit wasn't going to arrive for another few days so I brought a sample of my water into my LFS. While there I saw a pair of black ice clowns I really liked so I got those and put them on hold along with a blood red cleaner.

 

The owner finished testing my water and was very condescending to me about the fact that my tank still had ammonia and nitrite in it. I explained to him the tank was still cycling, maybe he was just having a bad day. Anyways, he sold me this "go juice" which looked like a cup and a half of this maroon/off red colored liquid. Told me it was the bacteria that break down ammonia and nitrites. 90% of my brain told me its snake oil but I bought it anyways to see if it would make a difference. I tested my water last night, about 3 days after my visit to the store. My ammonia looks to be between 0.25-0.5ppm, nitrite 0.25ppm, and nitrate 5-10ppm. I'm not sure what to do at this point. I don't want to add these expensive fish if there's a chance they could cause a spike. What would you all recommend I do? I attached pictures of the test results.

 

Thanks

[ReefSafeSolutions]

It seems like the bacteria he sold you is helping a little bit. What I'd do is order those API test kits so you can test daily and make sure your water is safe for fish. The bacteria isn't complete snake oil...it doesn't work as fast as manufacturers say it does, but I used bottled bacteria on my tank and it cycled in about 2 weeks. Much faster than if I wouldn't have used it.

 

But regarding your cycle, it's not quite done. You still have ammonia present. So when your ammonia gets down to 0, see how long it takes for nitrites to get down to 0. I'd imagine your ammonia will be at 0 in the next 2-3 days and your nitrites are low enough, so when ammonia does get to 0, dose a tiny bit of pure ammonia, about 1-2ppm (I've only been able to find it at Ace hardware, and there are calculators online that will tell you how much to dose to get to 1-2ppm). Don't go nuts with the ammonia and add too much or you can kill the bacteria that is establishing.

 

Anyways, when you get to 1-2ppm of ammonia, test ammonia every day after you dose it and see how long it takes to get to 0. Also test your nitrite to see how long it takes to get to 0...but the real concern is ammonia. Once your tank can process out the ammonia in 24 hours, you should be safe to add those fish. But no reason to rush it, once you're there you may want to give it another week or so just to be safe. Your nitrates will probably be getting high-ish as well at this point, so do a water change after you reach this point.

 

I hope this doesn't confuse your further...let us know if you have more questions!

 

EDIT: Also don't let the fish store owner bug you...nothing wrong with buying fish and keeping them in his tank for a while. The incremental cost for him to hold the fish is literally nothing, he should be stoked he sold you a pair of sweet clowns!

[Kellie in CA]

Your tank is on it's way, but needs more time. I always count on at least 6 weeks until I add anything live to the tank, then I start with just a clean up crew and I see how that goes for a few weeks.

[ajmckay]

Once you get the basics down "the cycle" is easy to understand. The cycle is simply establishing a population of bacteria that can convert organic waste before it becomes toxic to the inhabitants. I think a better way to say it is "establishing the biological filter".

 

How long it takes your tank to cycle before it's ready for inhabitants depends on the following:

 

1) How much organic waste is being produced in the new tank (often called the bioload). Before you can add inhabitants you must allow all dead organic matter to decay and break down. Unfortunately Pukani rock has a ton of dead stuff stuck to it. Clean it off as best you can to speed up the process. It's the best rock IMO so people often powerwash it or soak it in vinegar for several hours then power wash or hose off.

 

2) How much bacteria is in your tank. If you start a tank with 100% clean dry rock there will be only a small amount of the right kinds of bacteria in the tank. If you were to add a fish now the organic waste it produces would take a long time for the bacteria to break down since there are so few. Look up bacterial reproduction (also called cell division) to see how bacteria multiply. You basically have 2 options to increase the amount of bacteria in your tank to make it ready for fish. You either grow it yourself by way of ammonia dosing or slowly ramping up your inhabitants (instead of a fish, add a snail first which the bacteria will be able to handle, then next week add more inhabitants, etc... each week ramping up the amount of waste being produced in the tank by a small amount and letting the biofilter catch up). The other option is to add bacteria in large numbers by using a bottled bacteria product which is probably something like what your LFS guy sold you. This instantly adds large amounts of bacteria to the tank so you can stock quickly. In your case, however, you may still be reading ammonia because the rock is releasing organic waste into the tank as the bits of dead stuff decompose. IME the best way to scientifically confirm that your biofilter is capable of supporting a population of typical reef inhabitants is to dose pure ammonia to about 3ppm. Test again in 24 hours and if there's no ammonia then you can be sure that you're good to go. No guessing or wondering. Search ammonia dosing to find a simple calculator of how much ammonia to add.

 

Each time you make a change to #1 you have to consider #2. This is where understanding bacteria reproduction comes into play. The larger the capacity of the biofilter the quicker it can respond to larger changes to the bioload (level of organic waste) in the tank.

 

Also it's useless to wait X amount of time because on the flip side if the tank runs out of nutrients then the bacteria die off. Waiting can be counter-productive.

 

Finally - it's common for API ammonia test kit to show a false positive... So that might play a part.

 

Good luck

[Alexervin239]

Thanks for the help! So from here it would seem like the best course of action is to go pick up some pure ammonia and dose the tank to 2ppm and see 24 hours later how much has been converted to nitrites/nitrates?

[Alexervin239]

Another thing I was wondering; does the amount of light the tank receives during the cycling period make a difference? I've been dealing with Kessil and don't currently have a light over the tank. I may not have one back up for up to a week. The tank gets a lot of natural light as it is (I've actually been meaning to fix that but it may not be an issue right now).

[reefone]

Thanks for the help! So from here it would seem like the best course of action is to go pick up some pure ammonia and dose the tank to 2ppm and see 24 hours later how much has been converted to nitrites/nitrates?

no. don't dose anything. your tank is still cycling.just let it run for now. as stated dry live rock has a bunch of dead stuff in it that's still breaking down. the last thing you need to do is add more ammonia to it. light does not make a difference in the time the cycle takes. I like to keep the lights off during the cycle.

[Alexervin239]

Okay, I still have some SeaChem stability left, should I continue dosing that until I get to the full 7 days? At this point I'll leave the tank alone and test every day. Once Ammonia is completely gone and nitrites are to 0 my tank is cycled correct? Its just a waiting game now I guess.

[ajmckay]

Thanks for the help! So from here it would seem like the best course of action is to go pick up some pure ammonia and dose the tank to 2ppm and see 24 hours later how much has been converted to nitrites/nitrates?

You most certainly can. The high limit for ammonia where bacteria start being poisoned is observed to be between 5 and 8ppm. So adding ammonia to your tank won't harm anything if you stay lower than that (there's nothing in your tank to harm!). Chances are you still have a steady supply coming from the rock at this point still though so while you probably can't expect ammonia to be 0 after 24 hours you can see how long it takes to get it back down to what you're seeing now. I think it's fun to test stuff like this though and while it can't hurt it can certainly give you more practice at testing your water and also a more practical understanding of how the nitrogen cycle works. Also it's a vastly better method than just waiting a month or whatever and then adding inhabitants and then if something goes wrong wonder what happened.

 

Another tip to help cure the rock faster (cure meaning rid it of all dead organic matter) is heat up the tank. The increased heat will further help mechanically to loosen and break down stuff. Just remember to turn the heater back down when you're ready to add inhabitants.

 

 

Another thing I was wondering; does the amount of light the tank receives during the cycling period make a difference? I've been dealing with Kessil and don't currently have a light over the tank. I may not have one back up for up to a week. The tank gets a lot of natural light as it is (I've actually been meaning to fix that but it may not be an issue right now).

Light does not matter at this point for you. You have nothing on the rock that needs light since it's dry base rock.

[Clown79]

tanks take time to cycle. Depending on the method chosen, depends on length of time.

 

Liverock cycling is by far the fastest.

 

With dry rock its longer, especially if you didn't dose ammonia.

 

Until the ammonia processes to 0 and nitrites are 0, the cycle isn't completed.

Once those are down to 0, a waterchange can be done. Then you can add the fish. I wouldn't advise adding all 3 things to a newly cycled tank though.

[ajmckay]

Okay, I still have some SeaChem stability left, should I continue dosing that until I get to the full 7 days? At this point I'll leave the tank alone and test every day. Once Ammonia is completely gone and nitrites are to 0 my tank is cycled correct? Its just a waiting game now I guess.

It's up to you. The stability will boost the biological filter but it doesn't really matter because you're just waiting for what's on the rock to break down.

 

Yes, in your situation the tank is ready to start stocking once ammonia and nitrite are undetectable.

[Alexervin239]

Update: 2 days after that test the ammonia is 0.25pm, nitrites are 0, nitrates are 20ppm. What should I do at this point?

[brandon429]

your live sand brought a confusing component into the mix: the ability to generate nitrate off the ammonia you added.

 

you are doing a blended cycle...live sand (already cycled and able to run a whole tanks bioload) and dry rocks that weren't. You would simply dose with bottle bac and wait about a month then start reefing, because after 4 weeks under water + nutrients + bac added your rocks will have taken on a base bac layer fully functional, and the sand was already strong enough on day one. adding any ammonium chloride really sped things up

 

google your API .25 reading to see if interpretations vary on that .25, many see that as a zero too.

 

due to that discrepancy, we can use known submersion timeframes and not test kit guessing to know when you can begin. red flags go up any time any cycle shows .25 consistently, without change to any other reading. a month in the tank in the presence of live sand, and you can start your first few corals and frags and snails after a nice big water change.

[Alexervin239]

So would you recommend I continue waiting or should I do a 5 gallon (approx. 30%) water change? I have a pair of black ice snowflake clowns on hold at my LFS but I'm not at all interested in rushing things. I purchased the fish so they're probably going to call the LFS home for a few weeks. What about adding a few snails, 1 or 2 hermits, and a blenny to test the waters? I don't have a light set up over the tank but I see what looks to be diatoms on the intake for my HOB filter as well as a white film on my heater.

I say white, it's white/clear.

[ajmckay]

You need to wait until the rock is cured - meaning all the organic material on/in the rock has fully decomposed. Increasing the temperature can help speed up this process as can using a turkey baster to blow off the rocks daily. If any larger chunks of organic material come off you can net it out.

 

IME doing a water change now won't help or hurt anything really.

[Alexervin239]

Oh okay I gotcha, so I'm waiting for the rock to cycle now not so much the water. I've got a Tetra heater that is programmed to stay at 76 degrees F. I'll take a turkey baster and blow out as much dead material as I can and remove it. What are some signs to keep an eye out for that the cycle is making progress or is nearing completion. I was thinking ammonia levels going down would be an indication but they're already 0-0.25ppm. Nitrites are 0 as well so should I watch for spikes in those as well as a continued rise in nitrates?

[Clown79]

Water doesn't cycle, its the rocks that cycle. The rocks are your biological filteration and until the cycle is done the tank is unsafe for living things.