Just not happening

[GaryD]

Hi Jonathon,


I’m sorry Garry commercial aquaculture frequently recommends water changes to assist riding a system of unwanted algae blooms.That might be so in commercial aquaculture but it's not necessary in aquaponics. The only time I've ever had to change water is if ammonia or nitrite levels were dangerously high.


“The solution to pollution is dilution” The solution to pollution is not to get into it in the first place. The underpinning principle of aquaponics is to use the nitrogen cycle so that there is no pollution.


.....high carbon dioxide levels and other toxic byproducts which intern causes excessive stress on your fish shortly leading to death.....Cutting back the feed, straining out the fish solids, ramping up your bio-filtration and putting in more air will address the problem......but if you lose your nerve, you can always change water then.


Look most people will work it out for themselves but as Sunshine said “You can rationlise the cost on what 300 dead fish are worth”.In my experience, the large majority of fish deaths come down to a lack of oxygen. The simple solution is to get more air into the water.

Gary

[Jonathan Dyer]

For one we are not talking about the control of pollution before it starts; we are talking about what to do to overcome an outbreak after it has occurred. Yes it is always best to prevent it but Charlie has asked for some advice on that matter and that is what I’m discussing and explaining why.

I also said “you are diluting the algae bloom so it is less of a hindrance to control making filters more effective and reduces cleaning time (sometimes altogether) in order to remove its presents totally by appropriate means.” By appropriate means this implies “Cutting back the feed, straining out the fish solids, ramping up your bio-filtration and putting in more air will address the problem” that’s also why I said “good bacteria levels in your bio-filter are essential at this stage” as they are responsible for the decomposition of dead algae, worms in the grow bed also help no end in the break down of dead algae. Does Charlie's system have good bacteria levels? If not perhaps buying some bacteria starter and adding it to the tank will kick things along sooner rather than later.


That might be so in commercial aquaculture but it's not necessary in aquaponics. The only time I've ever had to change water is if ammonia or nitrite levels were dangerously high.

How is aquaponics any different? One you are growing fish, two you are growing plants if you ran your system poorly you would come up with the same problems; an algae bloom is a classic example it is due to poor management practices and the best way to deal with it once it has occurred is do a water change, supply as much oxygen as possible, increase the water temperature, and filter the water as best as possible, given a short time it will clear up nicely. I recommended algae killer as a quick and easy way to deal with the problem now (and by the time the fish are a year old the very weak chemical is non-existent in the tank), not wait three weeks for it to clear up by itself another option is barley straw but this takes longer. Your fish may be able to handle and survive all of the poorer conditions but there is always a higher risk of the fish dying due to the poor conditions.

There are benefits of the integration of the two (growing plants and fish together) that we all agree and understand explicitly but a well run commercial aquaculture enterprise follows the same principles and seldom water changes are needed as the bio-filter is large enough to cope with all nitrates produced (not every week as commonly done), in aquaponics the plants are there to consume nitrates as a source of food the fish are there to supply nitrogen to the plants intern purifying the water for the fish. Lets say I didn’t use the word "commercial" would recirculation aquaculture be any different?

[GaryD]

Hi,


Lets say I didn’t use the word "commercial" would recirculation aquaculture be any different?

The principal difference between recirculating aquaculture (commercial or otherwise) and aquaponics is that with an RAS regular (daily) water changes are a feature of its operation .....to rid the system of nitrates. With aquaponics, there is no need (in normal circumstances to do this because the plants use the nitrates.

How that water is used makes the difference between whether aquaculture is sustainable or not.


I recommended algae killer as a quick and easy way to deal with the problem now (and by the time the fish are a year old the very weak chemical is non-existent in the tank)
But that doesn't mean that it is non-existent in the fish. Some chemicals accumulate in fish meat.

Jonathon, I suspect that (with the exception of the use of chemicals) we are not so far away from each other on this matter. I'd change water if I felt that I had to do so to save my fish. If, however, I was sure that I was getting enough air into the water and that the pH/ammonia/nitrite levels were manageable, I'd simply restrict the amount of light and maximise mechanical and biological filtration.....and ride it out.\

Gary

[Outbackozzie]

I'd change water if I felt that I had to do so to save my fish. If, however, I was sure that I was getting enough air into the water and that the pH/ammonia/nitrite levels were manageable, I'd simply restrict the amount of light and maximise mechanical and biological filtration.....and ride it out.

I agree, run your pump as much as possible, shade the tank, and add extra oxygen to the water if required. Usually shade and pumping fixes all AP algae problems, very quickly.

Chemicals are simply not the answer, nor are they required.

[Murray]

Jonathan D,
I appreciate that the use of chemical fixes really does work, but there are lots of us who just do not want chemicals (man made synthetic or natural then manipulated) in our food.
Part of the reason home grown veggies and fish (Aquaponics) is on the increase is that we have been told for decades now about "safe" chemical additives etc to our food, and we just don't believe those claims any more.

Even ADD kids are now to be found in most part to be victims of food additives, preservatives colorants and the like. (How did they try and cure the ADD problem caused by chemicals....give em a drug, another chemical)

Maybe some folk swing back a little too far against chemical additives, but you sure can't blame them.

Remember the Thelodomite babies ? (spelling not sure)
That was a very safe drug....so we were told.....

[DaveOponic]

I don't have a problem with algae since I put sucker fish in my ponds. The sucker fish spend their time removing algae and have done a great job. there is so little algae on the bottom and sides of the pond that the suckers now surface with the Koi and Tilapia at feeding time and compete with them for pellets.

I do get some algae inside the hoses and at the top layer of clay pellets in the grow bed. As I am in the tropics, my system is under heavy shade cloth and my pond is a concrete pond at the end of the verandah.

The sucker fish are now huge and look more like Flathead. I have seen big ones for eating in Chinese restaraunts in Sarawak.

Dave

[GreenCow]

What type of sucker fish are you using? Plecos? Or, is there a particular one that is better than others?

[DaveOponic]

I'm not sure what species it is but here's a picture (attached) It looks like some kind of catfish to me, the kind that has a nasty barb on it's back. They sure can suck though! They are sold as Borneo Suckers in aquarium shops here in Brunei.

Dave

[Jason Palenske]

I was actually going to suggest an algae eater, they gradually reduce the algae letting the system slowly return to normal and not throw anyone into shock with sudden changes. It's pretty common here for aquariums and sometimes stock tanks.

[Jonathan Dyer]

Hi Jason, Do you mean the commonly called Chinese Algae Eater?

[Jason Palenske]

Actually for us here, just about any bottom feeding sucker fish is referred to as an algae eater. The gray pictured are similar to catsish, apparently called a plecostomus, in that they grow to fit their environment, there are however brown ones that resemble sharks that only grow to an inch or two. Which if my google search is correct are your chinese ones.

http://www.aqua-fish.net/imgs/fish1/chinese-algae-eater-11.jpg

Hope this helps. I've seen suggested from large fish farms that they allow small tilapia to range in unflowing pipes as they keep the algae down as well.

[Outbackozzie]

They also dont like cold temps, mine all started dying at around 15 deg c.