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Hi all,

Long time lurker, first time poster.

I started my system about 1 month ago. It's a rather small system (used the Ikea project described by Japan Aquaponics that's been circulating around the interweb). I've attached few pictures.

Anyhoo, there's 4 fishies (2 Platys and 2 Tetras). It's indoor so water temp is probably around high 60s. Water test 2 days ago shows high ammonia, high nitrite, low to nil nitrate. pH is 8.5. Growbed media is Growstone. Tap water test shows pH of 7.3-7.5 with hardness level of 3 (sorry, don't have units but I presume it's mg/L). No worms yet. Since it's indoors, I have a grow lamp on shining on the vegetation (variety of herbs) for about 10 hours / day.

Fishies are eating well, seems happy. Established plants seems to be ok and things are definitely growing (i.e. clipped few thyme, chives, green onion off and new stem/leaves are growing in). No germination of seeds except for chives and dill. The dill from seed and a recently transplanted established cilantro seems to start yellowing. After some research, I added chelated iron as well as some kelp extrat (used growmore because I couldn't find maxicrop locally).

Few questions:

1. how long does it usually take after addition of chelated iron before you start seeing plants undergoing chlorosis start to perk up again?

2. should I worry about the pH at all, or is supplementing chelated iron and kelp extract enough at this time? I lean more toward the camp of not chasing after numbers if things are looking ok.

3. is it normal for seeds to not germinate with what I described above?

4. am I being impatient or am I along the 'normal' curve before I see nitrate level rise and pH come down?

5. should I even do a water exchange at this time?

6. and lastly, just so I can understand the science behind this... Let's assume the water pH stays constant (I know it doesn't, but let's say it does), and there's no effect from the Growstones.. can the high pH level be attributed to ammonia and nitrite (which seems to be basic based on the Ka) while after having an established system, the pH will come down due to Nitrate?


Thanks in advance!

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Hi there EH. The grow stones may very well be raising your pH...or they might not be. Before testing your tap waters pH, let it sit out for a couple of days in a glass (or whatever). When you test 'right out of the tap' you will get a false (low) pH reading. So try that first before you go batty trying to figure what's raising you pH so much...but yes, NH4/3 will also raise pH a bit.

The "hardness level" is most likely the 'ol German dH (degrees of Hardness) scale. 1 dH equals 17.8 mg/L. (ppm is equal to mg/L in this case...so mg/L and ppm can be used interchangeably)

 1) If you bought GrowMore's crappy Fe-EDTA chelate you might not see much 'perking up' at your pH level. EDTA (in addition to being a known plant toxin) is almost useless at that pH level. An Fe-EDDHA product is what you want. Fortunately GrowMore makes such a product. (Don't let the fact that most EDDHA chelates clock in at "only" 6% fool you. EDDHA products are more expensive for a reason)...

Added to the water you should see some effects within 48 hours or so...foliar fed, in about 12 hours if you're paying attention...

2) If it's not the Growstones, and it really is the dH scale...don't bother since your pH will be coming down soon enough

3) Yes and no. You can germinate seeds with spit...but only if it's a viable seed. Most seeds will have germination rates printed on the package (86% germination rate...98% germination rate)...age and how they were stored will effect those rates. Also, some things like lettuces sprout in a day or two, while others like hot peppers can takes weeks to sprout.

4) Yes, of course your being impatient...but who among us isn't? (OK maybe some of these guys doing AP in India or Japan can be all Zen and patient about cycling...IDK)...Relax it'll happen...actually wait, before you relax...would you mind listing your actual water parameter numbers instead of using terminology like "high" or "low"? Such terms really have no meaning (other than to the person using the term in the first place) if you think about it 

5) See that last bit in number 4...but probably a 1/3 water change may be in order soon...Again, real numbers would be helpful to anyone of us trying to help you...

6) Yes, ammonia (NH4/3)  is basic...and does raise pH a bit (but try off-gassing the CO2 from your tap water first by letting it set out for a couple days, then test the pH). The pH won't really come down "due to nitrate" (NO3) per say, however, it will come down from aerobic bacterial respiration from the N. Spira that is oxidizing nitrite (NO2) to NO3. For every 1mg of NH4 that your bugs oxidize to NO3 they "use up" roughly 8mg's of carbonate alkalinity (which is where that dH/kH comes into play) and about 4.5mg's of O2. So it is the by product of bacterial respiration itself that will neutralize alkalinity and hence bring pH down over time, not the NO3 itself. As they do there thing and 'breathe', our bacteria create carbonic acid (H2CO3...which is really just CO2 dissolved in water)...this acid is the mechanism by which pH is lowered. (It is also the same thing responsible for you "false low" pH reading when taken right from the tap).

In the case of tap water:

CO2 + H2O --> H2CO3

After that the carbonic acid reacts slightly (and reversibly) in the water to form a hydronium cation H3O-+ and the bicarbonate ion HCO3-

H2CO3 + H2O --> HCO3- + H3O+

This little tid bit may hopefully save you some head scratching and headache/frustration and resolve concerns about your media, or whatever...

There is also a diurnal pH swing phenomena due to algae and CO2 respiration. At night algae use O2 and give off CO2 (which again is a mild acid, so it'll lower your pH reading)...during the day they use up much CO2 (which inversely will raise your pH reading)... Take a reading at dawn...and take a reading at dusk, and compare the two...

In the case of bacterial respiration it (a simplified version) would go something like this:

55NH4 + 76O2 + 109HCO3- –> C5H7O2N + 54NO2- + 57H2O + 104H2CO3

(which just means to say that ammonia is combined with oxygen and hydrogen carbonate to produce bacterial cell mass, nitrite, water and carbonic acid)...Then along come N. spira (which is really the main nitrite oxidizing bacteria and NOT N. bacter in fresh water eco systems)

400NO2- +NH4 + 4H2CO3 + HCO3- + 195O2 C5H7O2N + 3H2O + 400NO3-

(which is like saying that nitrite is combined with ammonia, carbonic acid hydrogen carbonate and oxygen to produce bacterial cell mass, water and lots of nitrate).

Hope that helped you somewhat, to as you say, 'understand some of the the science behind this' 

Got these readings from the API test kit (sorry for the lack of units):

pH 8.4

Ammonia 0.25

Nitrite 5

Nitrate 10

Your ammonia they can live with...Nitrites are pretty high though. It might be prudent to do that 1/3 water change. and while you're at it, salt your system to 1ppt (parts per thousand). Although salting is best used as a pre-emptive strategy to mitigate nitrite toxicity, but it will hurt nothing and will still help some if you salt now (after the fact). 

And since you actually seem interested in learning about your new hobby...here is an explanation of why and how chloride salts combat nitrite poisoning http://www-heb.pac.dfo-mpo.gc.ca/congress/1994/tomasso.pdf

Plants will be more than fine with that level of salt. Strawberries are sensitive and start to suffer above 3ppt. In terms of the fish and nitrites...what they are after is the chloride ions...so, it makes really good friggin' sense to use a combination of plant beneficial salts instead of the typical sodium chloride (NaCl) that most aquapons use...

2parts NaCl : 2parts KCl : 1part MgSO4-7H20 (also known as Epsom salt) (should you find it more economical to use magnesium chloride [MgCl] instead of epsom salt...cut the amount by 2/3rds...since Epsom salt is about 9.8% Mg by weight, while MgCl is contains about 3 times that amount of actual Mg...It's all about the balance when it comes to the cations)...

In addition to saving your fish from the negative effects of nitrite poisoning, this salting scheme will allow you to plant things like tomatoes, cucumbers, squash etc...and actually have them do well and bear fruit...or you can just follow the dinosaur method of salting with a plant useless (yet widely promoted) sodium chloride salt. It's your choice.

To find 1ppt...convert your total system water volume to liters. If you have 1000 liters, 1ppt would be 1 kilogram of salt. If you have 3000 liters of water, 3 kilograms of salt would get you 1ppt...if you have 8000 liters of water, 8 kilos of salt would get you 1ppt...I'm sure you see the pattern emerging here...

You only need to salt once a year or so. Don't do it every week or anything...That would be bad...

Oh yeah, and don't use salt from your cuppard, because it has iodine in it (bad). Go to the hardware store and check out the pool section or water softener section...DO NOT go to the aquarium shop, unless of coarse you want to buy the same product, re-packaged and sold at a 300 to 400% mark-up...(some people are really weird that way)...

Thanks Vlad. But why do all this to nitrite when you want to get nitrate from it?

You don't actually "do" anything to the nitrite...it's still there in all it's glory. All your doing is saving your fish from it's toxic effects (called methemoglobinemia). Nitrite is very toxic to fish. The salt doesn't affect the nitrite itself, just the 'receptor on the fishies gills' where it would attach to.

"6. and lastly, just so I can understand the science behind this... Let's assume the water pH stays constant (I know it doesn't, but let's say it does), and there's no effect from the Growstones.. can the high pH level be attributed to ammonia and nitrite (which seems to be basic based on the Ka) while after having an established system, the pH will come down due to Nitrate?"

EH, what is Ka?

And I agree with Vlad, your pH will probably come down on it's own if your KH is 3. Don't forget that source water is not always stable, and it will often fluctuate in KH and pH according to the season. Mine varies from 7.0 to 9.0, from spring to late summer, respectively. Depending on the time of year, I bring my pH down with acid initially, and regulate pH by either hanging a bag of coral chips, or not. If I don't initially use acid (when filled with hard water), then my pH would never come down. Source water plays a huge role in answering the pH questions.

Vlad, thanks for the detail on pH as related to nitrification. I have always thought the lowering of pH (which is an increase of free hydrogen), was simply from bacteria liberating a hydrogen in the process of converting NH3 to NO2? I'm sure it's not as simple as that, but it logically seams to me that the first bacterial process would contribute to acidification. The second process just adds another O, converting NO2 to NO3. I'd sure appreciate a link to a scientific paper so I educate myself better. Thanks, brother.
Ah, never mind the Ka question. I should have looked it up before I asked.
http://chemistry.about.com/od/chartstables/a/pkatable.htm

"...I have always thought the lowering of pH (which is an increase of free hydrogen), was simply from bacteria liberating a hydrogen in the process of converting NH3 to NO2?..."...

Yup, that is certainly true. Absolutely.

"...The second process just adds another O, converting NO2 to NO3..."

Yes, but so does the first process. Both "add O".  Ammonia to nitrite conversion is an oxidizing process which liberates some free hydrogen...But so does the conversion of nitrites to nitrates, as both are oxidizing processes. In both instances nitrogen looses electrons to oxygen and the free hydrogen 'lowers pH'. (I stuck with NO3 in my earlier post since that's the part EH had asked about. I didn't mean to give the impression that NH4/3 to NO2 was not acidifying, or anything like that).

I know we were only talking hypothetically, and we're all probably aware that when we talk (or write) about some of these processes that they are much more complex than we make them out to be. For one, they are not happening in a vacuum, but rather in a very complex, living, biological eco-system...So most of the time we're not getting anywhere near the whole story...actually we're not even getting near half the story...Take for instance these ammonia oxidizing processes...We are only so interested in them because we think they "suit some purpose" to our AP systems (obviously), but they (oxidation processes) are only exactly half the story. You can bet your bottom dollar that where ever there is some oxidizing going on, something nearby is being reduced. Oxidation is only a half reaction...Reduction is the other half...and hydrogen is the reducing agent. We can think of reduction as 'adding hydrogen' and/or gaining electrons (or we can think of it as loosing oxygen...Either way reduction and oxidation always go hand in hand (I really like the term redox since it reminds us that the two principles are very much 'married'...At any rate...

Both NH4/3 to NO2 as well as NO2 to NO3 are oxidizing processes "adding O" and "releasing H"...so both contribute to the creation of acids which then go on to neutralize (usually carbonate/bicarbonate) alkalinity in our water...usurping it's buffering capacity and driving our pH down...

I can try to dig up some kind of paper for you, but a lot of this stuff is about as fun as chewing on broken glass, and you wade through 25 pages of something in order to glean an understanding of the three paragraphs that are of pertinence, or interest to your AP endevours 



Jon Parr said:

"6. and lastly, just so I can understand the science behind this... Let's assume the water pH stays constant (I know it doesn't, but let's say it does), and there's no effect from the Growstones.. can the high pH level be attributed to ammonia and nitrite (which seems to be basic based on the Ka) while after having an established system, the pH will come down due to Nitrate?"

EH, what is Ka?

And I agree with Vlad, your pH will probably come down on it's own if your KH is 3. Don't forget that source water is not always stable, and it will often fluctuate in KH and pH according to the season. Mine varies from 7.0 to 9.0, from spring to late summer, respectively. Depending on the time of year, I bring my pH down with acid initially, and regulate pH by either hanging a bag of coral chips, or not. If I don't initially use acid (when filled with hard water), then my pH would never come down. Source water plays a huge role in answering the pH questions.

Vlad, thanks for the detail on pH as related to nitrification. I have always thought the lowering of pH (which is an increase of free hydrogen), was simply from bacteria liberating a hydrogen in the process of converting NH3 to NO2? I'm sure it's not as simple as that, but it logically seams to me that the first bacterial process would contribute to acidification. The second process just adds another O, converting NO2 to NO3. I'd sure appreciate a link to a scientific paper so I educate myself better. Thanks, brother.

Update on my system - haven't had to post/ask much since everything kicked in nicely. Numbers showed that the system has cycled. However, with the use of Growstones, my pH constantly stays up in the 8's - Independent tests outside of the system suggests to me that this is the culprit. Regardless, plants are growing nicely, and every 2 weeks or so, I just spray it with some foliar spray concoction I made with some seaweed kelp extract and chelated iron. All the plants seem to be doing fine.

That is until this weekend when I decided to change it up. Because I was using the "Ikea hack", I was using a tub for the fish. Since everything is going nicely, I thought I would change it to a tank so that kids can see the nice fishies. All the transfer went fine until I decided to transfer the gravel. During the transfer, stones/gravel were placed into a bucket that used to contain detergent. Long and behold, the tank became a graveyard. No bubbles or anything crazy like that, but trace amount seems to have done its job. When I finally realized the root cause, I went from 10 fish down to 4 in matter of 36 hours.

I've taken everything out of the fish tank, done a major water change (50%) and tried to let the water run through activated carbon where ever there's a water inlet. Planning on doing 20% change daily for the next week or so. After the major water change, what's left of the fishies already appears to be a bit more alert and energetic. I'm bracing for a complete wipeout, but I'll see what I can salvage before I am forced to break everything down and start from scratch.

Anyhoo, here's a question out of all this... From what I read, what kills the fish with soap/detergent is that it gets all up into the gills and get rid of the slime that they need to breathe. What other damages does detergent cause to the fish and is it reversible?

Where did you buy that rack (drawers) set up for your system? I'm looking to set up a small system for my wife in her classroom (teaches first grade), for her kids, and that should be perfect.

Jacob: Ikea. Search Google for "Ikea aquaponics". I believe Japan Aquaponics is the main source/creator, but I personally found the instructions more helpful on Instructables. The only downside with this set up is that you can barely see the fishies, which is something that I would think kids will like to see. In fact, demise of my system described above was an attempt to make the fishies more visible for my kids.

Update on my stupidity. After stabilizing, casualty count of the FT was: 10 fish down to 3, 4 shrimps down to 2.  Since then, I've added few tester guppies and all survived. In fact, I saw few fries in the tank yesterday.

Thanks for the info. Do you think a ten gallon glass fish aquarium would fit in the bottom section?

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