No aerator update

[Kobus Jooste]

It is now going into autumn, and I can now confidently state that the system configuration that I was testing - having no aeration originating from an electronic aerator, has been a success.  I have not lost a fish (40 tilapia in 1000 liters) at all, and always managed to operate with a DO well within the limits of my fishes' tolerance.  While the fast-flowing water have caused some issues such as reduced fines retention in the gravel, I have been able to keep most of the plants I tried happy, including a tomato in a raft bed.

 

I feel confident that cascades can be used as a viable alternative to pumped air in any setting where electricity use is a major concern.

[Averan]

awesome!

i've been taking the same approach with my micro balcony system, but after noticing some signs of fin rot on my new koi i'm going to try pumping in air to encourage more aerobic bacteria and discourage the anaerobic bacteria that are the cause of the ailment.

can you recommend any cheap DO meters?

[Kobus Jooste]

My DO testing comes in the form of an aquaculture photometer unfortunately.  You do get some basic aquarium kits, but these have some nasty chemicals in them.  I'm not that in tune with what is available at a fair price where you are.  In South Africa, good brands include Sonde and Hanna, with a whole lot of cheaper brands out there that I know very little of.  You can also look at integrated units with probes in your water reservoir, but these are high end - Sonde, Aquatronika etc. 

Averan Gale said:

awesome!

i've been taking the same approach with my micro balcony system, but after noticing some signs of fin rot on my new koi i'm going to try pumping in air to encourage more aerobic bacteria and discourage the anaerobic bacteria that are the cause of the ailment.

can you recommend any cheap DO meters?

[TCLynx]

yea, not sure "cheap" and "DO meter" really go together and still get you much in the way of reliable results.  There are DO test kits available but not the safest of materials out there or the easiest tests to run and reliability probably very dependent on price and your skill using the kit.

[Averan]

that's sorta what i gathered.

bummer though, as i'm not inclined to 'invest' in a DO meter yet with only a tiny little AP system.  wouldn't mind a crappier option that isn't toxic.

[Jay Wolf]

TC hit it on the head.  DO meter and cheap don't go together.  But here is what I can tell you.  I purchase a high end DO meter 12 years ago and it still works great.  At the time, it cost $650.  I send it in once a year for a tune up which costs $50.  For me, knowing what my water chemistry is worth the small amount of short term capital, in order to ensure long term savings (aka dead fish).

TCLynx said:

yea, not sure "cheap" and "DO meter" really go together and still get you much in the way of reliable results.  There are DO test kits available but not the safest of materials out there or the easiest tests to run and reliability probably very dependent on price and your skill using the kit.

[Jay Wolf]

@Kobus - I am still a big believer in our trickling tower biofilter that has spray bar.  We already have to pump the water up in our vertical system, so we take advantage of the spray bar trickling tower.  I will have to send you a picture of it so you can see what I am referring to.  Obviously, using this simple step gives us plenty of DO and there is no need (except for backup in power outages) for electronic aerator.

[Kobus Jooste]

I think anything with a spray bar ort a trickle tower effect is a great way to add DO, and I'm still of the oppinion, although potentially wrong, that you get cheaper aeration from a larger water pump and spray / cascade than with a smaller pump and an aerator.  I'll be adding 10 trickle towers, basically 110 mm pipes with cheap media in them, to may larger system soon in order to stop needing aeration there (and to get the nitrate production shifted elsewhere but that is a whole different issue).

Jay Wolf said:

@Kobus - I am still a big believer in our trickling tower biofilter that has spray bar.  We already have to pump the water up in our vertical system, so we take advantage of the spray bar trickling tower.  I will have to send you a picture of it so you can see what I am referring to.  Obviously, using this simple step gives us plenty of DO and there is no need (except for backup in power outages) for electronic aerator.

[Chris Smith]

My first aquaponic system is built on terraced land. I have three troughs at different elevations so my water is always tumbling down hill. The water picks up lots of oxygen as it is falling. I recently noticed that my air pump had died at some point but the system is still perfectly happy since the falling water picks up all the oxygen that is required.

My 400 gallon fish tank to the right had a 4 output aquarium pump to aerate the fish. I realized early on that I did not need much aeration in the tank since the water was picking up so much oxygen in its travels. Since it has died I do not notice any difference in growth or any affects on the fish.

I have to use a larger water pump to raise the water from the sump to the fish tank so my power savings on aeration is used in moving water from the sump to the fish tank.

I am in the process of removing the middle trough in this system and reconfiguring it into a gravel bed to be used on a different system. I have vertical towers, NTF  and media buckets to replace the trough and use up the rest of the unused terrace space.

[George T]

I intend to use an indexing valve and it occurred to me that part of the cycle of indexing could be sessions of spray directly to the tank.  That should increase my DO levels and I have other reasons for planning this as well.  I also intend to use the cascades/spray bars for draining back to the tank.  Although I'm not opposed to the use of aerators, it makes sense not to be dependent upon one and in this regard I'm thinking of aerator failure, power failures/backup power supply.  If any possible improvements on this concept occur to anyone, feel free to expound.  Good topic.

[Averan]

The more low-tech the solution, the more reliable and cheaper to operate.

I'm experimenting with replicating natural designs, turning my sump into a wetland marsh habitat complete with O2-producing aquatic plants.  I think that if you can turn every outlet flow into a waterfall of some sort with maximum aeration then all these little efforts will add up and help to improve overall system stability.

The less commercial the system, the easier to make these outflow aerators decorative and visually attractive.  The more commercial the more you have to come up with a technical version that fulfills the same function, but might not look so pretty.

@George:  you might consider a permanent bypass to spray/aerate the FT, if your pump has enough power left over to divert some flow from your beds.

[Alfred Luckerbauer]

Have a waterfall without additional aeration for over 10 years on my koi pond.  Plant and fish are doing great.S- Florida is very hot in summer ans it still works very well.

[Kobus Jooste]

Lovely set-up Chris.  I'd love to have a slope like that to play with!

Chris Smith said:

My first aquaponic system is built on terraced land. I have three troughs at different elevations so my water is always tumbling down hill. The water picks up lots of oxygen as it is falling. I recently noticed that my air pump had died at some point but the system is still perfectly happy since the falling water picks up all the oxygen that is required.

My 400 gallon fish tank to the right had a 4 output aquarium pump to aerate the fish. I realized early on that I did not need much aeration in the tank since the water was picking up so much oxygen in its travels. Since it has died I do not notice any difference in growth or any affects on the fish.

I have to use a larger water pump to raise the water from the sump to the fish tank so my power savings on aeration is used in moving water from the sump to the fish tank.

I am in the process of removing the middle trough in this system and reconfiguring it into a gravel bed to be used on a different system. I have vertical towers, NTF  and media buckets to replace the trough and use up the rest of the unused terrace space.