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Anoxic filtration???


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6BF924A4-6F20-4F6E-A1E9-ABB417AA21DE.png.7ca5bf33827606527c63cc352545005c.pngA87B8CBF-3CEB-4953-B803-AA053AC12AC7.png.207a456698dc3ea14cda0e8a1ef2f8e0.pngFFD88ADD-972A-4C16-AB0A-8DDD769AAB6F.png.9e3421979b2f800b2a37bb3b75c4f607.pngHello and Thankyou for this forum to explore new ideas and information 🤩

what’s the hype all about - I believe it’s just new and not a lot is known about it, like anything it takes time and a little experimenting if you have the time, nothing more nothing less. 

So this is a little of my experience with it and I still have a lot more to learn so if anything I write is wrong or incorrect please let me know as I am new to this as well . 

I have been following this anoxic filtration for a while now and have done a few experimental tanks/ ponds myself. Thankyou to R Budds I thought I would share my journey and experiences with it.

As I stated I am still quite new to the whole concept of it but I have a basic understanding of how it works thanks to a few of Dr Novak’s  informative videos on utube. ( and yes they can be long winded but worth the watch ) 

I keep mainly goldfish, so anyone who keeps goldfish would know the struggle with filtration and keeping good water quality and low nitrates. I was doing water changes twice a week to maintain these nitrates.

I have a 500 litre and a 200 litre patio pond. I keep 4 in the 500 showed in the photo and in the 200 litre I keep 2 pearl scales , the bristle nose pleco and guppys which hitched a ride with plants and now have made quite the family in there along side my pearl scale gold fish. 
I run a bog on both, after trying canasters , internals etc these have kept my waters crystal clear, and best maintained, and I was after something to help with my nitrates levels, and Bogs also help to reduce nitrates. ( Oz ponds were my go to utube videos regarding bogs) 
Initially my bogs ran to fast to be effective, bogs need a slow flow to be most effective. This is when I also found out about the anoxic or bcbs by Dr Novak.

They also need low flow and low oxygen zones to be most effective. After doing  little research I found that the bacteria living in these particular zones is specific to these conditions ( low o2, below 0.5 parts but not quite 0 parts.) and will take o2 from the nitrates as well as phosphates in the water , and harmlessly gas off , which then reduced the nitrate levels in the water. 

So bogs also have a anoxic zone because of the slow flow through the gravel, but I was using pea gravel. 
Baked clay/ zeolite and laterite ,  which is Recormended, ( baked clay/zeolite for its porous properties and laterite has iron) have specific properties as well which help house this bacteria and the iron help the bacteria to colonise quicker. 
I removed all gravel and added a mix of baked clay/ zeolite and laterite in my bogs.

I also added bcb baskets with the same clay and laterite to both of my ponds, I also diverted some of the flow from the main bog into smaller tubs with the same material. This slowed the flow in my main bog filter and gave me two forms of filtration using one pump. 
I know this whole anoxic filtration has created a lot of questions and is dismissed as to hard or difficult to create, or the question about reducing the oxygen levels in the tank etc but this is not the case. The slow flow and low oxygen levels only need to be in the filtration or filter, much like your plenum. Which I also now run, or undergravel filter. The only zone that needs to be low in oxygen is under the actual gravel or plate. Or in the filter itself. Once the water enters back to your tank or pond it it fully oxygenated again. 
The baskets or bags are great for this, in the actual bcb basket or bag is where the action happens, the bacteria or baked clay  in these baskets attrack the ammonia and nitrates because of the baked clays negative charge. 
Anyway these baskets are very easy to add especially in ponds , but also in a tank with a plant if you prefer , there is absolutely no reduction in o2 in the pond at all it all happens in the basket itself. No plants are need it is all bacteria but plants definitely make it more pleasing to the eye. 

It basically reduces the nitrates and phosphates and helps create the full nitrogen cycle, not just the ammonia to nitrites to nitrates and from there we usually have to water change , as we have always known it. 
personally I still like to water change as it is not only nitrates that need to be removed, the water also depletes in other minerals over time. But it  makes it is a hell of a lot easier and a lot less stress for me that my nitrates are not building daily. Especially with goldfish.

I have not lost a fish to disease, my waters are so much more stable and clear, and personally this has been totally worth the research and time to slowly change over my system. Sorry it’s a bit long winded but it’s hard to explain everything clearly and I hope this makes sence or incourages other to give it a go. Its well worth it and your fish will love it.

Only this moring my big mumma Goldie spawned again , like clock work she is and the same with all the fish I keep. 
My bristlenoses had to be seperated for some time out, as they two would spawn after spawn, and well guppys they need no encouragement to spawn anyway. 🤣 

A few Photos of a couple of them, I also have a few tubs around the yard now that also have bcb bags which keep my tubs clear , no air or filtration in those tubs and all have shrimp thriving .Shrimp  Probably added accidentally when I dump my fish poop water into them. I grow extra plants and duck weed in the tubs so that is the reason for the poop water in the tubs. 

Again thank you to R Budds 👍🏼 and happy fish keeping everyone , Thankyou also to aquarium co op for this platform to explore and learn from others 🥰




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