Backyard Aquaponics
A place to discuss aquaponics

What can be removed from an AP system and how. Is gassing off a solution for dealing with spikes and controlling cycling of younger systems. Or for dealing with pump failures. What can be removed and how. eg Ammonia, nitrite and nitrate.

That's not an easy question Duff
Offgassing or outgassing, when it relates to AP systems, is usually to remove excess carbon dioxide from the system to allow more o2 to be dissolved. It is also used to remove free chlorine from water before adding to systems.
It only relates to 'dissolved' (loose term) gasses which have not combined with other elements, in other words it has to be a gas in its normal state. Water can only hold so much 'gas', for our purposes we would prefer it to be mainly o2.
Technically I think you could offgass ammonia, but it combines readily with other elements and we need a bit. Nitrites are fairly unstable but not a gas, neither are nitrates.
Problem is all the 'life' in the system is continually changing the state of things.

Dont know about gas [well in the bed i am an expert ] i still say the more air you have in the system the more stable it becomes

"i still say the more air you have in the system the more stable it becomes"
No argument on that one, only thing left are the nitrates and thats stick in more plants

Search RSG filter if you want a way to off gass excess nitrates but this really isn't needed except in systems with minimal plants to use the nitrates.

In general you can off gas chlorine if that is what your water is treated with (you can't do this with chloramine though) and you can off gas CO2 like from water that has been just drawn up from a well. If getting really technical, I believe Ozone needs to be degassed from the water before returning the water to a system but I don't know if any of us are using ozone sterilization in any of our systems so this probably is only and idle note here.

In my larger system the pump moves 8000ltrs and hr and if it failed depending on the amount of fish and time for a new one to get here there could be a big problem. If I can use the air blower and a lot of air stones to remove a lot of the ammonia then I would not have to do a lot of water changes and upset the fish. Also the air blowers can be used on a battery system. Smaller pumps to keep a little water moving through the GB's for the bacteria. Larger FT are main reason I was interested in this. A 50% water change in my tank is 27500ltrs and the cost of the water is not the real problem. It is the amount of chlorine in it. Has anyone used spinning disks, I've seen them in greenhouses to create mist.

Still reckon zeolites for an emergency Duff and use a 12v bilge pump.
Blowers as well if you can manage it.

The name rings a bell. Does it break down if its in a system too long. I'll have to google it. But it might be the easiest option. How fast does it work.

Simply blowing air in won't take care of the ammonia or nitrite long term.

During say a power failure, air can keep the fish alive for a day provided no feeding gets done.
In the case of a pump failure, the air could keep the fish alive for a day but ya need to get the water going through the bio-filter as much as fast as possible and avoid feeding. Some backup small pumps might not be optimum but could help reduce the need for water changes.

Interesting stuff. It take the ammonia out and you soak it in salt water to recharge it and remove the ammonia. May not work if your system is salted. And can be easily connected to the outlet of the GB's so it does not remove the ammonia before the bacteria get a crack at it. Could make the cycling a lot easier in untested system designs.

TC he has over 50k FT and not enough gbs at this stage.

Duff you can get zeolites easily, they use them for swimming pool and spa filters. They work by ion exchange and adsorbtion so ammonia removal will be dependant on how much water is changed through them.
BTW how did the ETS skimmer go? If you got it working well DOC's and free floating algae should be clearing. And at a lower rate of flow it should be an efficient offgasser.
I don't bother, bubbling water (or water changing now for that matter), Have rigged up an extra line from the garden retic system to spray water into the top pond when its doing the garden as a top up.

I have not checked the filter yet. But the water coming out of it looks a lot clearer than the other out lets. I've got it set up so the flow can be turned off and on. Between it and the silvers the algae is going.

I might have some zeolites in the sand filter. Before I stopped using it I had it filled with bags of course filter material from the pool place. Was crap to use because they stuffed the valve and it got every where. Will have to check. Might just need activating.

Ammonia and Nitrite can be off gassed relatively easily.
Google is your friend.

http://209.85.173.132/search?q=cache:tRPAjkEXmboJ:www.mpks.org/articles/BryBateman/TrickleTower.html+off+gassing+ammonia+koi&hl=en&ct=clnk&cd=5&gl=au

There is lots more links like that too, mostly regarding koi.

you woke me up, Duff, (and made my day ):
this thread emphasizes one of the advantages of pumps over blowers and airstones:
the ability of pumping over (or from) a biofilter
especially important in a backup system

and over a trickling tower, which can be wide and shallow instead of high and narrow

where mist is concerned:
I have built automatic disinfection systems for the food industry where a whole factory was automatically sanitized by a procedure called "fogging"

the method I used was with compressed air and special nozzles that create an ultrasonic effect through a resonator
not suitable for a backup as a compressor needs a lot of power

another method for fogging is high pressure (>40 bar, preferably >100 bar) and special nozzles
big problems with clogging as the nozzle orifices are extremely small
also not suitable for a backup as a high pressure pump needs a lot of power

spinning disks are a third method for creating mist
never used them, but there might be some possibilities in there, thanks for the suggestion

last method is ultrasonic fogging
at the time this was too expensive to install
but nowadays some small units are sold for people with respiration problems
maybe check on these

one warning about fogging: Legionella !
unless some disinfectant is added
H2O2 might be a good one: it disintegrates into water and oxygen
very efficient disinfectant
1 to 3% solution is enough

frank