Backyard Aquaponics
A place to discuss aquaponics

As almost everyone on this forum knows, there is a limit to what nutrients fish and/or crustaceans can produce to feed plants. the main nutrient left behind by fauna waste is nitrogen, namely in the form of nitrates which are nitrified by bacteria into nitrates, or ammonia, which is also nitrified.

Now I dont know if this information is widely available, let alone on this forum. I for one spent quite some time tracking down this information in regards to dosing of nutrients to optimum levels.

This will be my first real contribution to the forum since joining but a few days ago. So...here it is:

The dosing calculator:

After a lot of searching around the web and being involved in various planted aquarium forums, I was directed to this site.

Calculator


Scroll down to the bottom of the page to download and enjoy.

The basic concept of this calculator is to allow its user to input a certain quantity of raw fertilizer (agriculture grade) into a set amount of water volume. (Make sure to check off "direct dry ingredient dosing")

The calculator will show how many ppm each fertilizer will add to the water volume.

(This of course should be done after adequate measurement of what is already in the system)

More to come! Please, ask questions as well!

Prepare for many posts disagreeing with you!!!!

i know that there are far too many posts to read though and maybe this info is buried in there

This is the way it goes, yes N is the Major nutrient supplied by the fish (but correct me if i'm wrong, but if you add up the NPK for for veg growth and NPK for fruiting, N will be the greatest requirement.

Anyway, i digress. what we have found is that by leaving the solids in the system we believe that they get mineralised and release P and K to the system. It was always quoted that aquaponics was only good for leafy greens and i believe that is true for a system that removes solids. Most people here have NO PROBLEM fruiting plants (with great success).

I have even seen a very new system that has trouble fruiting, but then no problem on the second year with adds further weight to the theory of solids mineralization in the bed.

No one i know of here has added fertilizer except for a bit of seasol very early on in the piece.

hope this helps

Steve

Yep, constant tomato production from my big system at home thats 3.5 years old, with no fertilizers added...

Fayes system is 6 months old and has been producing many tomatoes and peas. My new system is less than 4 weeks old and already has chillies and capsicums starting to fruit, it's produced strawberries and the tomatoes are flowering already...

the diet of the fish can be manipulated to produce a desired poo formula specific to the needs of the plant at stage ~ just need to do more research on that process give me about 4 years

Thanks for the link J5, don't take the comments too personal, all info supplied is relevant...it is digested by the multitudes and we all have an input...from this greater improvements have been made in the BYAP world

So thanks again, don't be deterred... AND DON't FORGET TO WASH YOUR GRAVEL

nah no way, didn't mean to attack, sorry if it came off that way

More proof.... I havn't had any significant fish 'crap' in my system for 4 months now. I have 5 marron and 2 swordtails...

I have a roma tomato bush with 4 tomatos, a cherry tomato with over 20 fruits and a normal tommie with a few fruit coming on now... I planted them only 2 months ago, they are healthy and strong plants.

That growth is all based on the solids that are breaking down slowly in the growbeds. It also serves as a reassurance that between fish batchs all my plants won't die off.

I'm regularly (1x/month) adding a little chelated iron, and have recently found that a tiny bit of phosphate helps, too. Frankly, these tilapia eat such low-protein food that I don't think there's a lot of extra nutrition to get passed through in their poo. I do agree that there is a limit to what the fish can produce.

no offense taken!

i still have alot to learn about aquaponics and how it differs from submerged plant propagation and production. i posted the calculator so that people would be able to use it In Case they have a nutrient deficiency and need to supplement, not that they necessarily have to.

I have found that with very high light conditions and an overload of nitrogenous waste that algae becomes a problem in other parts of the system, especially in pipes. Having the optimum conditions for the plants i.e. optimum ppm of nutrients, CO2, and light stop algae growth and plants explode with growth.

I have class but Ill be back shortly for more discussion

Janet, any chance of incorporating some scoria into your system?

Think I'm going to take one for the team....bought barra pellets as my intention was to grow barra this time around...unfortunately this fell through and I have SP on the higher protein pellets.

Will be keeping an eye on the water quality and will also cut back on chelated iron dosage, while monitoring the plants

Difference in protein levels:
SP pellets 35%
Barra 44%

SP on steroids

Les, our jades and silvers have always been on barra pellets, no choice in the matter

Aha!...the larger lote of SP have been on the SP pellets up to a week ago, so I should be able to notice any difference (that's if my seeing-eye dog and cane are handy)

...and Steem (and his mates) don't decide to take a lightning trip to Bris to visit me

I'm working on adding oyster shell and egg shell, Steve. Scoria is expensive here--used to pot up orchids and as heat diffusing material in grills. I'm not so lucky as DT--to have my own volcano handy.

Maybe I shouldn't wash the gravel. That would leave a lot more minerals in the system...

Les, I have been feeding my SP barra pellets from day 1 too...