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Greetings everyone. I purchased a system from Sylvia many months ago, but had to do some prep work before going ahead...that prep work being, getting a greenhouse up. Well, that's finally done, and this past week, I assembled the whole thing, filled it with water, and am now in the process of cycling it.

Yesterday was day one. The setup is complete and operational. The unit is in the greenhouse.

On day one, I added the dry mix included in the cycle kit.

On day two (today), I first tested the ph (8.2) and the ammonia levels (8ppm). Immediately after this, I added 5ml (2 tsp) of ammonia from the cycle kit. I did not check ammonia levels after this, but it seems to me that I was already starting out with 8ppm of ammonia, that adding ammonia would boost the levels even higher… I assume that as nitrites and nitrates climb, ammonia will go down? At what levels should I be concerned with if ammonia keeps rising?

2. I was watching one of Murray's videos, and the question I have is… Is the ideal way (with a flood and drain system such as Sylvia's) is to fill the grow bed up to about an inch under the top layer so as not to expose the top layer to water… thereby inhibiting algae? Then if so, and I had a better timer, would it be better to simply allow the water to reach the desired level, and then to have the timer switch to off? Or, is it better to allow the water to flood the bed for a full 15 minutes?

Thanks! and I'm sure i'll have many more questions.


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Provided you don't add any more ammonia (and there are no fish in there) the ammonia should not keep rising unless you are adding something that will convert slowly.


Drawback is that 8 ppm of ammonia is a bit high and could slow the process down.  I would probably not recommend more than a 4 ppm dose for the initial start and then wait for that to go down before doing smaller does from then on but I don't know Sylvia's new kit so you might be better off following her instructions.


As to cycle timing, provided your stand pipe keeps the water from flooding over your media if you just let the pump run for the full 15 minutes, then the more water that can flow through your bed the better for the bio-filter.  Actually, there is some evidence showing that running a system constant flood (just leave the pump on full time) through the initial cycle up phase may actually speed the process.

Thanks TC... I'll report back in the next few days if I have ammonia issues. In your opinion, should I continue adding the ammonia daily, or try to get the levels below a certain level and maintain that?  From what I understand, the bacteria need the ammonia to convert to the nitrite/ates. If so, I should expect levels to naturally go down...correct?


As to your cycle timing response...

By allowing more water to flow through the bed for a longer period, does that not subject the plants to root rot, etc?  Would more frequent "fill and drain" be more beneficial than less frequent "flood and drain"? It would seem to me that you are exposing the roots to even more oxygen, but less exposure to nutrient dense water...

signed... A little confused.  ;-)


Thanks again.



DON'T add any more ammonia till the ammonia levels drop.  (I actually think ammonia of 8 ppm is too high for cycling to really get going, I would probably do a water change to get the ammonia down to say 4 ppm and then leave it alone for a while till it falls more naturally.)  I would not add any more ammonia until you see the level drop below 1 ppm and then when you dose again you don't want to dose much since too much ammonia will hinder the bacteria that take care of the nitrite.  Your goal in fishless cycling is to be able to dose to 1 ppm of ammonia and have both the ammonia and nitrite get to 0 ppm within 24 hours, once you reach that state, then you can call it "fishlessly cycled up"  keep dosing small amounts (less than the 1 ppm dose) to keep the bacteria alive until the day or two before you will get the fish.  Stop dosing and let the ammonia and nitrite drop to 0 before putting fish in the system.


During this initial cycle up we are concerned with getting the bacteria up and running and are a little less concerned with the plants.  Once your ammonia and nitrite levels are down to 0 then you can worry about fine tuning the timing to keep the water quality good while also providing the plants with what they want (aquaponics is always going to be a balance with some compromises.)

Hi Jim.  TC is right...don't add any more ammonia if you are at 8 ppm now.  We actually changed the instructions for the system within the past few months to reflect targeting the lower ammonia levels that she is referring to (I'll send you a copy).  I honestly don't think 8.0 is a problem (all my systems hit that level when they were cycling) but you want to kick back and not add any more until you are seeing 2 - 4...then keep it steady at 4.  Test for it daily, bring it up to 4.0, then when both ammonia and nitrites plunge back down to zero by the next day you are cycled and good to go.


As for the water levels, the AquaBundance system is designed for 175 liters of media, which will fill it right up to the top.  There  is an inner lip in the grow bed that is not only there for structural reasons but is also just about the point where the water will rise to.  You are absolutely right that you want to keep 1 - 2" above that dry to prevent algae.  I recommend running on the timer (15 on / 45 off) for all the reasons you listed...namely your plants will have much more oxygen and be happier in their new home overall.


Glad you are getting your AquaBundance system up and running!

Hi Jim,

If you want to do efficient cycling you should do a 50% water change. At 8ppm your system is in crisis and too high for any bacteria to survive anyway so the water change TC suggested will bring you down to around 4ppm and the bacteria will start faster.However It will eventually come down to 4ppm over a longer time if you leave it this way it's your choice. We have a lot of info you can read,on this, in a discussion by Sylvia here..........

Hmmm... not sure what the "crisis" is, Harold. My approach to fishless cycling is based on the work of Dr. Chris Cow. Here is what he says about it on a bunch of aquarium forums "With that in mind, I'd like to propose a different recipe, which was suggested by D_Man and others (thanks!): Add ammonia to the tank initially to obtain a reading on your ammonia kit of ~5 ppm. Record the amount of ammonia that this took, then add that amount daily until the nitrite spikes. Once the nitrite is visible, cut back the daily dose of ammonia to ½ the original volume. One advantage of this method is that the ammonia spike occurs immediately... when adding 4-5 drops/10 gal/day, it could take 4-5 days before the ammonia reaches the same levels. This should result in an acceleration of the entire process, though by how much (on average) remains to be seen." While ~5ppm is certainly less than 8ppm, I've never seen any alarm about being at higher levels. Can you and/or TC point me to where you are getting the 4ppm rule from? Thanks!

I don't have any exact papers to point to that show the ammonia over a certain level inhibits the process but I do know that a really high ammonia level can stall things.  I've had people tell me they have read papers that said an initial dose of 5 ppm can help speed the process.  As to not going over that, well perhaps part of it is that you get too much higher and it will get hard to know what the exact level of ammonia is.


I've managed to cycle systems fairly quickly only dosing to between 1 and 2 ppm and I haven't been able to see an appreciable improvement in cycle time when I've dosed higher but I also don't see any problem with making the initial dose between 4 and 5 ppm.  I would not go to 8 since that is as high as the test goes and there would be no way to know if you had actually dosed way higher.

I definitely accept your excellent point about being at the max level of the test kit, but I'm still skeptical about a crisis being created at 8, especially with this guy with a PhD in Organic Chemistry saying that the optimal target is 5.  But, like I was saying earlier, we now suggest that customers target a 4 and it seems to be working well.


I actually gave up on running cycling tests in my greenhouse for a couple reasons.  First, unless one is running side by side controlled tests with some redundancy (at least 2, preferably 3, of each scenario and a control) it's pretty tough to reach a conclusion because there are so many factors that affect the speed of cycling (temp, O2 levels, pH, water quality, and what is flying around in the air).  Second, I figure after a couple years of running nothing but AP systems in there that I have so much nitrifying bacteria around that just about anything would quickly cycle!  

Hi Sylvia,

I realize the word crisis sounds much too dramatic,sorry. What I meant was, at 8 ppm bacteria slow and can start to die if ammonia level is maintained for some period. At this stage you'll have to wait a long time for Ammonia levels to decline. His readings were at Ph 8.2 an 8 ppm ammonia to which he added! No telling how high it's been.Over 10ppm means bacteria will die. So looking at all this, to be absolutely sure, it a good suggestion to do a water change(TC suggested).This will save time for cycling. See this

Thank you all for the discussion and responses! It's interesting to note that that level of ammonia was achieved using only the dry packet labeled cycle kit #1.  It was with this only cycled for about 18 hours before I took the measurements.  I then added 5ml more of ammonia. I will not add any more per all of your advice, until the levels come down. I work in a school where there is a "Trout in the Classroom" set up. I think I will borrow a few used filter pads and throw them in the tank for a day or so...  Hopefully, that'll help establish a friendly bacteria environment that will stabilize the system... whaddaya think?



Great idea, Jim.  Since nitrifying bacteria actually need a surface to cling to I'd probably stick that filter pad into the media instead of throw it in the tank...easier surface-to-surface trip for the little buggers.  


The #1 bag contains both powdered MaxiCrop and ammonia.  Let me know if you decide to pump off a bit of your water to dilute down the ammonia and I'll send you some more of the powdered MaxiCrop.

Sylvia - I'm not familiar with your cycling kit at all, but over here, we have always cycled up a system (aquarium) with a mix of ammonia source and bacterial cultures.  Is that what your kit does?  In a natural development cycle, the presence of each chemical triggers the development of the bacteria evolved to "deal" with said chemical, resulting in a 3-peak graph of chemical peaks - Ammonia, then Nitrtite, then Nitrate.


When you are adding chemicals to cycle, things behave a bit different from typical natural patterns, and when you add beneficial bacteria cultures, you can often cycle in less time.  bio filtration in aquatic systems can be extremely complex, with widely divergent data set cited by different authors.  This is so often based on differing research methodologies of chemicals used in research.


I have attached two recent papaers by authors including Losordo, whom I consider a very knowledgeable author on the topic.  The papers clearly illustrate that filtration characterisitics differ between using true aquaculture wastes and chemicals, and it also gives a nice spreadsheet of all the variables that you can consider when looking at optimal functioning filtration units.  Bio-filtration is one of those tricky topics where there is a lot of variation in data and a lot of people stating widely divergent data either from personal research or from forum discussions.  I thinik it is well worth going back to aquaculture publications and figuring out what the key points are for yourself if you have the time.  One of those factors that had got me in discussions here before is the minimum load needed to get a filter working.  Not only for cycling up but to maintain the bacteria in the beds once you have it operating. In the spreadsheet, it is listed as just under 2 ppm (1.8). It is therefore clear that loading a system from between 2 and 5, which seems to be the standard thinking in AP cycling, is on the money.  I don't personally think that there is an inhibitive effect from higher ammonia lebvels but it will be rather pointless to create those as you will have to wait for the water quality to drop to fish levels before you will be able to continue.  The nitrifying bacteria will bloom to deal with the high load, and then just die back to reference level once the standard ammonia loading of your system settles.


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