Pee-Ponics Flowering - Struvite

[Vlad Jovanovic]

Meir Lazar got me thinking...pee-ponics philosophy...

When he asked how to add P or K to his pee-ponic system(s) for his flowering fruiting plants, I gave him a "standard" answer coming from a organic hydro perspective...Rock of Phosphate, Bone meal blahblahblah...but suppose you were a vegan? Or, the idea of using an unsustainable post peak mineral did not appeal to you? OR, you really were trying to stay within the bounds (of an as of yet non-existent) "pee-ponic philosophy"...Many of us choose not to do things that we are 'philosophically' out of tune with...or at least do them less, and attempt to choose when and why we do them, wisely...

Dosing your system with (N-P-K 11-1-2) humonia in order to get the 'required' or desired phosphates for flowering just isn't an option because of the massive amount of N you would be simultaneously introducing. I'm sure everyone is well aware of why this is bad and whatnot, so we wont get into that here...But, if you could extract all those phosphates, without all the N... that would seem like a mighty fine addition to you arsenal of effluent. It turned out that this wasn't a 'new' idea or anything (but what is these days?), this is what I did...

After researching why my cat gets bladder stones, the idea came to me...I added Mg in the form of Epsom salt (MgSO4-7H2O) to humonia, stired, strained. The white gunk I strained off is drying in the sun. That white stuff is NH4MgPO4-6H20-ammonium magnesium phosphate and is called stuvite (it's the stuff that bladder stones are made of). It is basically a phosphate precipitate. Like the whitish grey gunk (Calcium Phosphate) that builds up in your mineral hydro system over time causing you to have to flush the media...only instead of CaPO4 this is MgPO4...and 'ya made it yourself..!

According to the Swiss, this struvite should have an N-P-K value of 6-29-0 (Mg-10). AND...

...the effluent (liquid) that is left over from the process has a lowered N value, very little to no P value, and a high K value. Seems like a match made in heaven. This should really open up your fertilizing options while sticking to using 'sustainable humonia'...A 3 part hydro nutrient all from humonia. Whoopie!

Struvite dissolves readily in even slightly acidic environments, and slower in slightly alkaline environs. (might be a nice slow release fertilizer for the garden too). [edit. since writing this, I've used the MAP crystals in both the garden as well as in a couple of small bio-ponic test systems. The phosphates appear to be immediately bio-available to the plants (unlike say, bone meal). The potassium rich leftover looks promising, but the weather has precluded me from being able to test that out much on cultivars that are real potassium hogs...So more to come on that next spring/summer.]

I pretty much just did this last night and this morning and am still testing out some details, but it looks promising. I'm keeping notes of weights, measures, time...and should have some conclusions soon. If Meir or any one is interested I can post a 'how to' with details, measurements, and pictures. I'm building a 12 litre 'struvite reactor' out of galvanized sheet metal and pipes I have lying around (cuz I have lots of humonia to process and building stuff is 'fun'). But really all you need is a bowl, a stick, and a piece of clothe...

(and no explosions or highly caustic stuff with this one either...and 'skill level' is as easy as it gets. If you can make sugar cookies, you can pretty much do this. For now, just getting to the idea, seemed harder than executing it).

For the (so far) theoretical math there is this thread...http://community.theaquaponicsource.com/group/chemistry-math-and-aq...

And for some other struvite stuff there is this... one...http://community.theaquaponicsource.com/forum/topics/humonia-and-st...

I'd like to keep this thread (hopefully by culling some of the cream of what comes out of those other two) about how to make and use struvite and the results when used to grow plants...

[Eric Warwick]

It's funny when I'm vague. 

[Bob Campbell]

@Vlad - When aging urine for humonia, is it OK to keep the solution capped?  I've been aging urine in 2 liter bottles for over a month and it just occurred to me that it might need oxygen.

[TCLynx]

I always sealed it up, wouldn't want to accidentally spill it.

[Vlad Jovanovic]

Naw, your fine. I keep mine nice and tightly capped. If you want to know weather the urea has converted to ammonia you can take a pH reading (about 9 or slightly above pretty much means it's done).

[Meir Lazar]

Just want to post a warning that dawned on me the other day. If you are keeping (30-50) gallons of urine around, you may want to consider keeping it outside or using tightly lidded caps that won't gas (unlike milk jugs). Having ammonia gas leaking in your house is not a good idea. If you smell something funky, move it outside. Just a common sense thing.

[Vlad Jovanovic]

I've not noticed any of my jugs or barrels ever 'gassing'...actually quite the opposite. The couple times that I've left a jug half full and forgotten for many months, with fresh urea it seemed to have depleted a bit of the air inside rather than expand/gas...

But still, a good idea Meir...

[Pat James]

Guess you guys are not married.... My wife is not fond of me accumulating a couple days worth of urine under the bathroom

sink, much less gallons or for months....

[Vlad Jovanovic]

Hehe...yeah she's pretty cool about it actually...Though once it gets to be more than 5 or 6 gallons of it hanging around in the bathroom...she does get on my ass to go put 'em in the storage barrels in the shed...

[Meir Lazar]

Yeah my wife is not fond of it. That's why I put mine downstairs...until I realized that the milk jugs are terrible for keeping the ammonia gas contained. But to be fair, there was over 40 gallons in containers...

[Eric Warwick]

I think threads like this may be the cause of the gender-imbalance on the aquaponics community. Although, it was TCLynx that started this all. 

[TCLynx]

Gender equality only requires a funnel in this case.

[Eric Warwick]

I just laughed for a good 10min--still laughing!

TCLynx said:

Gender equality only requires a funnel in this case.