Aquaponic Gardening

A Community and Forum For Aquaponic Gardeners

this is a site for the aspiring aquapon to post their questions and have them answered by the more experienced members.  No question is too basic!  This is a great opportunity to tap into advice from some of the most experienced growers in the country.  Go for it!

Views: 1093

Reply to This

Replies to This Discussion

Sylvia Bernstein said:
If I'm really in a rush I'll use aquarium water conditioner to de-chlorinate. Rupertofoz, what is your opinion of those de-chlorinating conditioners?

I'm not a fan at all Sylvia... indeed I'm not a fan of most aquaria related products and disease treatments... because....

They're often "ineffective"...

Often result in other side effects, which in turn provoke other "corrective" additives...

Many are carcenogenic to humans, even by exposure...

Most are designed for exotic "ornamental" fish that aren't intended for human consumption... indeed most are banned in aquaculture...

Most people aren't aware of correct dosage rates....

Most assume a continual regime of water changes... to diminish any harmful effects.... whereas a "closed loop" system like aquaponics might actually compound any harmful effects and/or uptake into fish flesh...

And it leads to a mentality of treating your system like a giant "test tube" or chemical laboratory...


To be specific about chlorine/chloromine "neutralisers"... and excuse the long post and chemistry lesson...

Products such as "Ammo Lock" are often advertised as...

"Ammo lock is actually a water conditioner that neutralises chlorine and chloramine by blocking ammonium ... i.e ... it is used to keep chloramine stable from turning into ammonia. "

Not quite...

Chloramination involves the addition of anhydrous or aqueous ammonia (NH3) before or after the addition of chlorine (HOCl) to produce monochloramine (NH2Cl). This reaction is as follows: NH3 + HOCl = NH2Cl + H20

(Chloramines also form to a lesser extent during conventional chlorine treatment when aqueous chlorine reacts with natural organic nitrogen... which is why we suggest bubbling chlorine treated water before using it for system top ups)

Ammonia exists in two forms, namely, un-ionized ammonia (NH3) and ionized ammonium (NH4+). The un-ionized ammonia is what is harmful to fish...

Both forms are measured together and are referred to as total ammonia. Standard test kits measure total ammonia (ammonia plus ammonium) without distinguishing between the two forms.

Chlorimine ultimately breaks down into the un-ionized form of ammonia.. it's source component..

Ammo-lock contains sodium thiosulfate pentahydrate. Ammo-lock works to detoxify ammonia and remove chlorine and chloramines.

It locks up ammonia in a non-toxic form (ammonium) until it can be broken down by the tank's natural biological filter and/or used by plants.

The older "Amquel" or "Ammo-Lock" products, while neutralising the ammonia, do NOT leave it readily bio available for the nitrifying bacteria

Please note, most ammonia test kits will still show ammonia present in the form of NH4 after using this product or in areas where chloramines are used.

PH plays a part, as ammonium dissolved in water will only remain ammonium while PH is low (acidic)... in the presence of alkaline water, the ammonium will be converted back to ammonia....

pH is a measure of the H+ ion ...acidic solutions have an abundance of this free ion..

Or in alkaline solutions the hydroxide OH- ion...

Free H+ ions bond readily to ammonia ... H+ + :NH3 → NH+4 ... to form the less lethal form of ammonium...

Which is why AP systems that run with low pH have a higher tolerance to TAN... total ammonia as we see in our tests... and the chart often posted...

When ammonia is dissolved in water, a significant amount of it reacts with the hydronium ions in water to give ammonium ions:

H3O+ + NH3 <> H2O + NH+4

The degree to which ammonia forms the ammonium ion depends on the pH of the solution.

If the pH is high (the concentration of hydronium ions is low), the equilibrium shifts to the left... the hydroxide ion abstracts a proton from the ammonium ion, generating ammonia...

So adding chlorimine to a system with pH higher than 7.5... will only exacerbate the conversion into ammonia...

Ammo-lock will simialrly breakdown in high pH solution... releasing the "locked" ammonium... into ammonia...

It initially locks the "ammonia" compounds of chloromine by actually lowering the pH... by several points in fact...

The newer versions of Ammo-Lock... Ammo-Lock2... are supposedly formulated to neutralise this pH effect...


Using Sodium Thiosulphate (ie "Ammo Lock") to attempt to treat chloromines in a system with fish... is the worst thing you can do IMO....

As is the use of any chemical dechlorinators... dechlorinators react with the chlorine portion of the chloramine. The chlorine is eliminated, leaving the ammonia free in the water.

So, if you use a simple dechlorinator that only contains sodium thiosulfate, you are solving one problem (chlorine) and creating a new problem (ammonia).

Most water supplies target 2-4 ppm Chlorine. Note that 4ppm of Chlorine is actually 5.8ppm Chloramine. (The Chlorine is 69% of the chloramine molecule, ammonia is the other 31%) So, with a possible 5.8ppm Chloramine, you have 4ppm Chlorine, and 1.8ppm ammonia.

Assuming a 1000 Litre tank

If you do a 10% water change, you would end up with 1.8ppm ammonia.

A 25% water change could give you 3.6ppm ammonia.

Bottom line... if you're water is treated with chloromine... don't do more than 10% water changes per week...
Hello RupertofOz,
I studied a fair amount of water chemistry while I was in college (not that long ago), but I rarely get to use it anymore.

I followed your post until the very end, when you said that "a 10% water change, you could end up with 1.8 ppm ammonia"

Let my try my hand at this math... If you change 10% of a 1000 litre tank, that is 100 l. If your water is treated has a concentration of 5.8 ppm of Chloramine (NH2Cl), or 5.8 mg/L, could have 5.8 mg/L * 31% = 1.8 mg/L of NH3.

Add 100 L of this, and assuming all of the Chloramine is broken down by your Ammo Lock, you have just added 1.8 mg/L *100 L = 180 mg of ammonia in your system.

Now you have 180 mg of ammonia in 1000 L of water, which is only .18 mg/L of ammonia once it is diluted.

Is this correct?

Couldn't you added the treated water into your sump, and give the ammonia time to dilute?

Also, what happens to the chlorine that was part of your chloramine? Does it build up in your system, or does it get used/ off gas?

Thanks,
David

N2S2O3 - This is the chemical formula for sodium thiosulfate, just in case you read it this was instead of "sodium thiosulfate"
David S. said:
Add 100 L of this, and assuming all of the Chloramine is broken down by your Ammo Lock, you have just added 1.8 mg/L *100 L = 180 mg of ammonia in your system.

Now you have 180 mg of ammonia in 1000 L of water, which is only .18 mg/L of ammonia once it is diluted.

Is this correct?


You're correct David, my bad.... moved the decimal point one place too many...

So yes... assuming you have no other ammonia in your fish tank...

If you do a 10% water change, you would end up with 0.18ppm ammonia.

A 25% water change could give you 0.36ppm ammonia.


Not seemingly significant amounts in themselves... but possibly dangerous depending on pH and water temperature of your fish tank... especially if you already have ammonia present...

Perhaps it's a good time to show the relationship of ammonia toxicity to pH and temperature... remember this is measured as TAN... total ammonia.... "un-ionized" ammonia (NH3 - toxic) & "ionized" ammonium (NH4 - non toxic)....

The values calculated above represent the toxic "un-ionized" toxic form... ammonia...

Un-ionized concentrations greater than 0.05 ppm should be handled with caution.

Adding 0.18ppm of ammonia.... might see your TAN reading > 1... (it's a complicated formula)
Attachments:
How do you calculate TAN from concentrations of NH3 and NH4+? Correct me if I am wrong, but this is how I would do it...

[(mg/L of NH3) + (mg/L of NH4)] / (14 mg/mole of N) = Total Ammonia as Nitrogen

It has been a while since I have done this caculation.

RupertofOz- how do you use the oft posted table?

I haven't totally read this page yet, but I think it is a good way to learn about ammonia.

David

http://edis.ifas.ufl.edu/fa031
David,

That is a good link that imparts much of the basics about the nitrogen cycle.
I messed up my TAN calculation. I think this is the correct version.

TAN = [(mg/L of NH3)/(mg of NH3/ mole of NH3) + (mg/L of NH4)/(mg of NH3/ mole of NH4)] / (mg of N/ mole of N)

That should get you mg/L of TA as nitrogen.

David

David S. said:
How do you calculate TAN from concentrations of NH3 and NH4+? Correct me if I am wrong, but this is how I would do it...

[(mg/L of NH3) + (mg/L of NH4)] / (14 mg/mole of N) = Total Ammonia as Nitrogen

It has been a while since I have done this caculation.

RupertofOz- how do you use the oft posted table?

I haven't totally read this page yet, but I think it is a good way to learn about ammonia.

David

http://edis.ifas.ufl.edu/fa031
Thanks a lot for the nice chemistry lessons there. I am listening in on all the posts trying to learn.
Also trying to read slowly the huge contents of the Backyard Aquaponics forums.

My update:
Finally found a source for 55 gallon barrels. $10 each and close to my work area. Will get this week.
When i am ready to put the water in how many inches from the top of the fish tank should i leave empty? i am wondering if i fill it up too much whether the fish will jump out?
Also considering some kind of net on top to keep cats out of the way.

Found a local pond that has fishes and plants in it - plan to use this.

The following submersible pump is available at Lowes:
http://www.lowes.com/ProductDisplay?partNumber=8430-48650-FP500&...

Is this good for my purpose? 55 gallon fish tank and 20 gallon growing media.
If so, how do we prevent the fish or other stuff getting sucked into the pump?

What brand of sealant can i use for the plumbing?

I did not find a electrical timer at Lowes that will switch on the pump for 15 minutes every hour for example. Any references for this will be helpful.
When choosing a pump, you want to look at the chart on the package (if they have one) that says how much water it will pump at the planned head height. So say the top of your grow bed is going to be 2 feet above the water level in your fish tank, then you want to see how much the pump can lift to that height. What if it is a barrel ponics set up and you are expecting the pump to lift to 6 feet you check that number. And then you want to make sure the pump will still circulate the amount of water in your fish tank each hour. If you are only running it 15 minutes an hour, then you have to do a little math. But basically if you have a 55 gallon fish tank, and you are only running the pump for 15 minutes each hour, you want to be sure your pump will move at least 220 gallons an hour at whatever height you are expecting it to lift the water to. There is no chart or performance curve on the lowes web site but on a guess, that pump will probably manage for you. Just make sure you have air running for your fish too.

However, I'm not certain that 20 gallons of growing media will be enough to support very many fish and you may find that the plants might not use up enough nitrates if you do have a lot of fish for the space so you might still need to do some water changes.

As to timers.

Here is a reasonably priced outdoor timer with 15 minute intervals. It is a mechanical timer and with the 15 minute intervals the levers are really tiny so you might need a tool to easily adjust which levers are on or off but you can't get much easier than this. Note about mechanical timers, they are not always super precise. However, for the price does it really matter that much if the pump runs for 15 minutes or 19 minutes each hour? Just keep it out of direct sun and it will probably work much better.
Roy, here is the 15 minute cycle timer I use, and like - http://www.amazon.com/Hydrofarm-Dual-Outlet-Grounded-Timer/dp/B001Q.... And I would add the same caution as TCLynx about the media - I've heard a good general rule is a gallon of media to a gallon of water, which is also equals out to approximately 6 gallons of water per sq ft of media. These are the measures I've tried to use and it has worked pretty well. Hope this helps
I learned to use Sodium Ascorbate (vitamin C ) for chloramines. It doesn't take much...seems to work.
Here's a few links about it...( I found them on a different aquaponic forum site. Sylvia, I don't know if I'm allowed to mention it's name ? )

http://www.sfwater.org/Files/FAQs/removal.pdf
http://www.swwrc.wsu.edu/conference/Papers/Greg_Peterka.pdf
http://www.dsm.com/en_US/downloads/dnp/51644_VitaminC.pdf

I'd really like to hear what Rupert thinks about it's use.....any pros or cons....?

RupertofOZ said:
Hi Roy,

Chlorinated water is usable in small amounts, if you have to use it...

Luckily, chlorine can be dissipated from water by exposure to sunlight and aeration. Adding a "bubbler" to a container of water for 24 hours is usually enough to make it safe.

The problem with tap water, is that some water suppliers dose with "chloramine" rather than chlorine...

Chloramine, while it does eventually breakdown through exposure to sunlight (UV), can't be dissipated by bubbling as chlorinated water can be...

And by the very nature of the compound, breaks down into ammonia or ammonium.... depending on pH...with possible fatal consequences to fish... or at the very least to an elevated "ammonia" spike in your system...

Indeed Chloramines can pose a risk for both human hemodialysis patients as well as fish. Chloramines easily enter the bloodstream through dialysis membranes and the gills of fish.

The most effective nonchemical method for removing chloramines is by activated carbon and certain spectrum UV wavelengths can also breakdown chloramine...
.
Activated carbon does not adsorb chloramines but rather removes them through its ability to act as a catalyst for the chemical breakdown of chloramines to innocuous chlorides in water.

This catalytic reaction involves the formation of a carbon oxide intermediate (CO*). This reaction is as follows:

NH2Cl + H2O + C* = NH3 + Cl- + H+ + CO*
David, never a problem mentioning other forums. We are all in this together!
Thanks Sylvia....just trying to be considerate.
I learned about the Sodium Ascorbate in the DIY AQUAPONICS forum. It was in the 'general' section....look for
LINKS & OTHER INFO, then the post ...."removing chlorine from tap water with Vitamin C?"..... if you care to read more about it.
It only takes a little. Rule of thumb/verify your self....1/8 of a teaspoon to 55 gals.

Sylvia Bernstein said:
David, never a problem mentioning other forums. We are all in this together!

Reply to Discussion

RSS

© 2019   Created by Sylvia Bernstein.   Powered by

Badges  |  Report an Issue  |  Terms of Service