Backyard Aquaponics
A place to discuss aquaponics

My thoughts for what they may or may not be worth

The molasses promotes the growth of the heterotrophic bacteria - different to the nitrifying bacteria usually used in AP (Nitrosomonas, Nitrobacter - actually obtain energy from the nitrification process itself).

From the article: "heterotrophic bacteria utilise organic carbon as an energy source and in conjunction with nitrogen to synthesize protein for new cell material". Which means the nitrogen is used and converted into solid mater - no longer available to plants!

What happens to this solid mater?

From the article: "creating high volumes of flocculated organic matter in ponds can mean that periodic draining of concentrated sludge is required".

It ends up on the bottom of the tank - could this be used on a dirt garden - probably quite well (and quite smelly).

So I would suggest that promoting heterotrophic bacteria, will have a significant negative effect on Nitrosomonas and Nitrobacter...

As mentioned previously, addition of a small amount of molasses would provide trace elements, so may well have some benefits in AP, but perhaps not those outlined in the article...

My understanding is that human manure is mostly (anaerobic?) bacteria. Extrapolating from that, I assume this is also the case in varying degrees for fish manure. If this bacteria is welcome and useful in the growbeds I see no reason that any bacterial sludge from the tank bottom would not similarly end up in the growbeds as food for the web of micro and macro critters there: bacteria, worms, fungi, and (sometimes) algae. All grist for the mill, grinding out nutrients that get used by our plants.

Yes, it may be that some nitrogen is temporarily tied up by the bacteria and might affect balance in short term, but things should come to a steady state soon enough. In fact, I would think that the more nitrogen is tied up in the web, the more resilient nitrogen (and other nutrient) levels would be under fluctuations in fish output. "Houston, we have achieved (hyper-)soil!"

SO, I see no harm in molasses, perhaps some benefit in short or long term.
As always, I reserve the right to be wrong on any and all particulars. *grin*
("Dude, I feel weird. Maybe it's the smoke. Do you think one of those fires hit a big pot patch somewhere?")

Hydro.... human manure might be processed by anerobic bacteria ....

Our AP systems are highly "aerobic" by design... and indeed great lengths are/should be taken to prevent "anerobic" processes... i.e unconsumed feed in the bottom of the tank... as this robs oxygen from our tank water... and can initiate algael blooms... further robbing oxygen from the system....

The amount of "solids" and fish "poo" isn't that significant % wise... and is dealt with by natural processes (perhaps anerobic?) within the growbeds.... worms help in this regard...

The essential process is however governed by the nitrogen cycle.... ammonia (respired by fish - 96%), urea (excreted by fish - 4%) > nitrites > nitrates..... by nitrifying bacteria colonising the growbeds.....

Maybe a little molasses... might have some benifit... if it provided some trac elements... other than that....

I don't see the advantages... but do see potential disadvantages.... maybe I'm missing something..... KISS principle surely

As I understand it (an I've had a few beers) every lifeform on this planet is carbon based. The assumption that bacteria only need nitrogen hydrogen and oxygen is I would have thought incorrect. Since we create artificial situations to replicate natural environments the carbon has to come from somewhere, probably decaying organic matter.
Still think its worth a go, in small amounts.

Yep... that's the "poo" that we pump to the growbeds....

Lets remember that the article is talking about aquaculture ponds with no active bio-filtration and trying to avoid toxic build up of ammonia when the algae can't take care of it all by it's self.

And now we should probably return Dons hijacked thread to him and if we wish to continue the Molasses debate, we should probably create another thread for it.

How much are you feeding now don and what are your readings like today?

Damn, don't sleep-in. lol
Sorry if I miss anyone.
thanks all for the feed back.
That's a lot of debate over simple sugar water.

With a bi-feeding of 115grams each, a slight change, if any, over test results of the 100g bi-feedings from the day before.

Ammo 0 to -0.25 or a trace
Nitrite 0 to -0.25 or a trace




Rupe & Zen... As to Nitrates... IMO plant nitrates are @ a point of imbalance, because of missing trace mic & mac nutes. An increase of these will allow the plants to begin to fruit in earnest. once a certain level of trace elements are archived, fruiting/Bloom will take over as Rupe suggests and the Nitrates will fall like crazy. Until then there will be bright green "New Growth" while older- pre-fruiting leaves and bud sets will stall and give up what they have for the new growth coming in. To that end, I bought some Maxi-crop Seaweed far from adequate but it's start.

Rupe, yes, I understand, when playing near the railroad tracks you could be hit by a freight train; especially if you're hugging & kissing a new girl. My Chi is centered.

Zen thanks for the offer bro. Maybe we could brew up a very weak batch Humic, Fulvic acids and add some EA (earth ambrosia), and just a splash Black-strap. If we can get a used I V bag...? We could run small IV drip over weeks and watch??? What would be REALLY GREAT... if we could ALSO get one of those Potassium Heart Attack V I Bags, hint hint... from a dead guy... that would be ok, right? lol

Oh yeah Chappo... soon, once the fish are feeding properly.

Since we're talking about IVs and sugar water... that's all molasses is, with some trace elements. In the hydro world we call it carbohydrates and plants love them because the fungus will go crazy as will plant up-take. In the symbiotic relation between certain bacteria and plants, certain bacteria/fungus (AM & VAM) exchange their hard work for plant sugars. The more sugars outside the symbiotic relationship/process the faster the Microbial growth. Millions of years of microbial evolution are not going to change cuz we introduced different Microbes. As mylesau said...


Nitrifying bacteria will ignore any sugar water present and go about their business.



Humus/humic and Fulvic acids break it down completely over time... adding to that tea color in your water, making it, again available to the plants. Those roots from 2 years ago you left in the gravel bed... today they are Humus.

TCL, those cucumbers from compost... Humus/humic acid (particially anyway)just add the calcium to your system and watch. It won't hurt.
Without Calcium

With Calcium


Check Mike please, he grows Monster Trees in the NM. desert to show what you can do with little to NO water. (good stuff) 10 short videos
http://www.youtube.com/user/soilhumic
I like this one... http://www.youtube.com/watch?v=xfTc0IyuO_0
http://www.soilsecrets.com/index.htm
Check his site for the school yard/playground projects he done. good stuff.

Note worthy:
Humus is the stable, long lasting remnant of decaying organic material. It improves soil structure and increases water retention. It's nutritive qualities include trace elements and several important organic acids but do not include nitrogen or phosphorus. (hello, No Nitrogen or Phosphorus... is that perfect for us or what???)

Search: "Sir Albert Howard" ( the father of Humus)

if you can overlook the dirt, see the growth and extrapolate to water and/or AP...
http://aquamor.tripod.com/KYOTO.htm Think of the human pee as fish poop. and it's ALL the same, less the water and fish. It's a good read, for those that can be reached!

thanks,

Zen you wanted O2 pics



all the air/ shots today the 11th.
http://picasaweb.google.com/sdismang/WaterAir/photo?authkey=m-TFB7zcNd0#s5221743311666379842

a YouTube feeding @ 80grams
http://www.youtube.com/watch?v=boxDm7Lji0M

You want that K++ bad! I'll keep my eye open for dead guys. lol...


I saw thoes cukes! I'll bring a fork!

Bit of a fan of Maxicrop myself Don.... flower/fruit set is very dependant on Potassium... a common problem in AP....

People have addressed it in several ways... from burying bananas in their growbeds ... to using Potassium Bicarbonate.....

Zen sent me some news... I guess I've been very lucky with the Calcium.

Hypercalcemia in fish is very easily done, and could be sudden death to any fish.

Good Morning/Night all

Numbers for 07/12
With a bi-feeding of 115g each, readings appear only slightly elevated over yesterday.




Ammo 0.25+
Nitrites trace to .25
Nitrates 70ish
PH 7.2
DO 100%+

I think I will stay a few days at this feed level.
Since I can't see the shades, three days @ the same fed level will make me feel better and the cats don't seem as rabid... trying to leap from the tank as I feed. This seemed strange behavior, is this a sign of hungry fish, fighting for food?

Nitrates are still falling off but the their rate of decline has slowed. I want to add this Maxi-crop seaweed and flip these plants to flower in earnest. This should drop Nitrate levels in kind.

Is there a consensus on the feed dose for Maxi-crop? Is there a set amount generally used by the group as safe in a ml to L ratio? I beg the same question of the Potassium found at my local Winery/brew shop?

All is watchful.
thanks

With the shells in our grow beds, we should have plenty of calcium in the AP systems for any fruit.

I can't say that I've had the problem of incomplete fruit fill out in the AP system because most of the plants don't get anywhere near the fruit development stage due to other problems. Not sure if it is due to and actual lack of some element in the system or just that the cucumbers need a low pH in order to use those elements.

BER blossom end rot in tomatoes and other fruit can also be a sign of lack of calcium (not had that problem with the AP tomatoes) but often there actually is plenty of calcium, it is just that due to erratic watering or too fast plant growth or some other problem, the calcium just couldn't make it from the roots to the fruit. Another thing that can cause incomplete fruit fill out is incomplete or poor fertilization which can also cause fruit drop since the plant doesn't want to expend extra energy on seeds that arn't fertile.

yep definitely think the idea of sticking to the current feed rate for a few days is a good idea.

I don't know what the dosage should be, hopefully some one will chime in. If not, does the package have instructions for using it as a foliage spray? If so, you could always follow those instructions and spray the plants (perhaps mixing just a little weaker than instructed to reduce chances of too much getting into the system.) Foliar spraying often gives fast results and can be a quick way to diagnose particular deficiencies since you should see some improvement within three days.

Maxicrop have many different products,,,which are you planning to use?

Some of them contain quite a bit of Nitrogen,,so maybe not such a good idea to add that when your trying to monitor your Nitrate.Initially definately go for foliar spraying rather than dosing the tank water,,,small amount and directly applied.

I've been waiting for the Molasses discussion to be seperated,,,,but whilst waiting have read maybe 20 studies on it,,,seems even the scientists cannot agree on which bacteria does what with the extra carbon,,but general concenses seems to be "a little is helpfull".