Vortex Aerator with Air Lift 

@robguyatt9602. Water properties are opposite, the solids will accumulate at the center, do an example on your own by stirring a bucket of water with some sand in it, stir with a spoon.

@robguyatt9602 - for mineralization of fish waste water or in making compost tea from worm casting there are two methods. 1) the classic bucket or trash can/bin aeration where you place air stones at the bottom of the bucket or bin. Here the air stones provide the oxygen (BOD) for the microbes to decompose the waste and keep the water aerated and moving. 2) using a vortex aeration the vortex takes place of the air stones providing the oxygen (BOD) for the microbes to decompose the waste and keep the water aerated. The physics of the vortex allows for natural aeration of the water to take place, hence one does not need air stones to aerate the water. A simple way to look at it is, as the water speeds up as it closer to the center of the vortex, more air is "pulled" into the vortex water column. With vortex aeration, you can either have a water pump create the vortex as it sucks water from the bottom of the bucket or bin and pumps it to the top of the bucket and because of the opening at the bottom of the bucket/bin a vortex is created. In this setup, one needs a sump for the pump to be placed in. The vortex bucket/bin drains into the sump and the pump pumps water from the sump into the vortex bucket/bin. In my case, I don't have a sump nor water pump but an air lift. The air lift lifts the water from the pipe at the bottom of the bucket/bin and then discharges it at the top of the bin thus creating a closed loop water cycle without the need of a water pump and sump. Less parts and pieces. As the air rises in the air lift pipe, it pulls the water with it. There are disadvantages to both systems but with the vortex aeration setup the farther the water is away from the center of the vortex the slower the water's velocity is. This is not advantageous because the water near the sides of the bin/bucket are not moving fast enough to have the particulates stay suspended in the water. So with this setup there will always be particulates at the bottom of your bin/bucket and if there is enough build up of particulates on the bottom, the mineralization process will turn anaerobic when you want it to be aerobic. This is why several times a day I open the drain valve and remove some of the particulates on the bottom. What I collect I put back into the system for further aerobic decomposition. Another disadvantage with vortex aeration with air lifts is that dissolved oxygen (DO) levels are not as high as the standard air stone aeration thus you are limited to the amount of mineralization or compost tea making your can achieve. A water pump and sump vortex aerator could possibly achieve higher DO levels but that would depend on the flow rate of the pump and size of the bucket/bin. To know for sure, one would need to measure the DO and calculate how much aerobic microbe decomposition one can achieve. When finished mineralizing or composting brewing, I open up the drain valve and fill my buckets with the water and let the particulates settle over 24 hours. Once the particulates settle, I have clear water to put back in my aquaponics. I then dewater the particulate sludge and add it to my homemade compost. The above answers your question but if you have more questions, please let me know. APOLOGIES for taking so long to reply!

@@sudeshramdhanie6216 Yes. That's why I have a drain to remove the particulates at the side of the bin. The drained particulate water is put back into the system. It would be better to have a conical bottom so I wouldn't have to do that but I wanted a cheap DIY setup.

@@sudeshramdhanie6216 Not so. The congregation in the center is only AFTER the particles have sunk to the bottom. The swirling of the waste laden water does cause the denser than water particles to go the the outside of the column of rotating water. This allows cleaner water to be extracted from the center of the tanks before the settling is complete. This is basic fluid dynamics which I studied as part of my Mechanical Engineering course. I subsequently worked as a designer of materials handling equipment which included dust separation cyclones for things like cement particle size separation and sawdust extraction systems for timber milling and wood working. The same principles apply whether the fluid is gas or liquid.

@@eskunkel Thanks very much for your detailed reply. So I was wondering how the vortex assisted settling when that's not the purpose but aeration is. Got it :) If you read my reply to @sudeshramdhanie6216, you'll understand my background and note especially that I have no experience in biological systems hence me thinking it was about filtration. Where I am right now and why I'm looking at Aquaponics is I'm keen to take it up as a hobby. I'm winding down my mechatronics business soon. My system will be based on my 1000L fish pond. It's been breeding Goldfish for decades but I got bored with them so being a Fly Fisherman I thought I'd give Rainbow Trout a go. Last September when we restocked my Son's farm dam I put a dozen or so fry in the pond and got rid of the Goldfish. At this time I have 3 Rainbows between 9 and 11" long. I am using a mechanical filter and pond pump in the pond. For the Nitrogen cycle I have several water plants in the pond and as Ammonia rises I just add an extra plant or 2. Currently Ammonia and Nitrites are trace amount. Before next September when we get the next batch of fry, I will build the grow beds and complete the system. Oh and I forgot an important factor between now and September. I will have a feed of home grown Rainbows. 😁

I’ve retrofitted my vortex aerator so I’ll upload a video about that upgrade.