Intensive fish farming with pure Oxygen

[canuckamuck]

I am busy planning an upgrade to my fish farming hobby, and I have been researching all manner of aquaculture ideas. I came across this video from an outfit in Florida stocking fish at the rate of 1 pound of fish per gallon (my calculation 120 grams per liter). They accomplish this by keeping an eye on the DO and keeping it around 8.

Now I am thinking that there would be a very high O2 expense by the time your fish got to market, but the electricity bill would drop considerably. Not too mention the compact size of the operation. You could have 3,300 market sized tilapia in an 20,000 liter tank. Which is about equal to a 5 meter diameter 1 meter deep circular tank. (rough calculations)

Of course you wouldn't have to go this crazy, but the addition of pure Oxygen has got me thinking. They say liquid O2 on their title, but surely they mean de-compressed liquid O2, as the liquid form is around -200 celsius.

Anybody else out there tweaking aqualculture ideas?

http://www.youtube.com/watch?v=X2BS6YLI4Gs

PS: I am seriously jealous of their drum filter, I would like to make one, but I can't quite get my head around how they seal the rotating drum to keep the filtered water separate.

[canuckamuck]

Sorry i didn't have a chance to see my post before the edit time ran out. The link you see is the link to the guys running the pure O2. I don't know why it didn't come up as a video window.

[IsaanAussie]

Where we used to live a Thai guy had a system of large circular tanks which he keep aerated with a plastic pipe bent and fitted around the inside of each tank. The air directed downward towards the centre. Some of this detris was pushed to the centre and out through the drain. He ran it with an aircompressor which fed all the tanks.

With your drum filter think of a one or two smaller diameter drum inside the outside one with a feed pipe in the centre welded to the bottom of the smallest diameter drum. Holes in that drum allow waste water under pump pressure to pass into the next size tank containing the first filter material and from there into the next and so on.

[canuckamuck]

Maybe I misunderstand you IA, but I don't think the drum filter works like that. the filtering is done right there on the first screen. The dirty water comes from one side of the box, goes through one side of the drum, and out the other and it is filtered on the way. The solids get caught on the drum and are blasted at high pressure through the side of the drum into a trough that shuttle them away. The screen on the drum in this case is 60 microns, but they make em as small as 10.

These drum filters are like$5000 and up, but I would love to copy one for a fraction of that. But it is the seal on a moving drum that does my head in.

[harrry]

Cheapest way of supplying oxygen would be an Oxygen concentrator. Available here for 20000baht (chinese made but good) They consume round 200 watt on average and supply 2 lpm at about 95% or 4 litres about 90%

[canuckamuck]

Cheapest way of supplying oxygen would be an Oxygen concentrator. Available here for 20000baht (chinese made but good) They consume round 200 watt on average and supply 2 lpm at about 95% or 4 litres about 90%

That is very interesting, I have never heard of an oxygen concentrator. You have given me something new to research.

[RedBullHorn]

Sorry i didn't have a chance to see my post before the edit time ran out. The link you see is the link to the guys running the pure O2. I don't know why it didn't come up as a video window.

Copy your link. Click "BB code" (third icon from the left next to "Font"), under "please select" click "Media"

and paste your link in the box of "Media URL" and click "OK".

[harrry]

Available through wheelchair type places....large pharmacies..the chinese is as good as the other or maybe even better as it is more serviceable.

[cdmtdm]

i just took delivery of my drum filter ex china ..good for 30,000 litres an hour, made from marine grade stainless and polymer , if u put both your descriptions together then u have the workings of the drum filter , i looked at making one, but for 130,000 baht landed it was not worthwhile imo ,,,,,as for o2 i think bottles work out cheaper ,,,,,

[xen]

Maybe I misunderstand you IA, but I don't think the drum filter works like that. the filtering is done right there on the first screen. The dirty water comes from one side of the box, goes through one side of the drum, and out the other and it is filtered on the way. The solids get caught on the drum and are blasted at high pressure through the side of the drum into a trough that shuttle them away. The screen on the drum in this case is 60 microns, but they make em as small as 10.

These drum filters are like$5000 and up, but I would love to copy one for a fraction of that. But it is the seal on a moving drum that does my head in.

I am trying to get my head around the drum filter. Does the drum spin and it is centrifugal force that separate the particles from the water. However the water would pass thru the drum filter and the particles would remain inside the drum which is different to what you are describing.

Many years ago there was a washing machine that was briefly on the market that was called a drum washing machine and that worked with centrifugal force doing the cleaning. I saw one in Robinsons in Sukhumvit Rd and they were very,very expensive. Made by Thompson.

[IsaanAussie]

Consider an easy way, get two steel recycled drums with clamp on lids one that will fit inside the other. The configuration is vertical so that the large drum sits on a stand. The two lids are drilled in the centre to fit over the vertical water feed pipe. The large lid is welded to the pipe a liitle above the smaller which is welded an inch or so above the end of the pipe. The small drum has a pattern of small holes drilled in the bottom. The small drum is 3/4 filled with filter media (my favorite - CRH Biochar) and then the drum clamped onto its lid. The large drum has an exit hose connected to its base and is clamped onto its lid. Water into the small filter drum and exits at its base into the empty large drum and out under gravity back into the pond. To clean it out, just undo the clamps and change the filter material.

A couple of extra thoughts. You may wish to add gussets between the lids and the water pipe, especially on the small lid to support the weight of water in the small drum. You may also wish to add a vent pipe in the big lid if you are running a high pressure pump. Rice hull biochar is a very efficient carbon filter for water .

[David48]

Made me curious also about the drum filter so this is an excellent website ... rotary-drum-filter

.

[IsaanAussie]

And a great piece of mechanical filtration no doubt. Applicable to where I live? What with the maintenance capabilities being a hammer and a screwdriver and the mentality of if it don't fit, force it, if you can't force it f'ck it. Oh,well it was old anyway.

I am more into biological filtration and locally available materials and parts. The automatic cleaning of my old piece of crap design is called a hose. The replacement filter is made in the back yard and the old stuff goes straight into the compost bin.

[canuckamuck]

i just took delivery of my drum filter ex china ..good for 30,000 litres an hour, made from marine grade stainless and polymer , if u put both your descriptions together then u have the workings of the drum filter , i looked at making one, but for 130,000 baht landed it was not worthwhile imo ,,,,,as for o2 i think bottles work out cheaper ,,,,,

I would love to hear a review of your drum filter. How many watts does it consume? Does it use UV? Do you like it?

I am still in the planning stages so I won't be buying anything soon, but I might pm you some day for the details of how you ordered it.

About O2, A 6 cubic meter bottle costs about 100 baht to fill, so I wonder if the Oxygen concentration can make 6000 liters for that price. I have my doubts, I also doubt they are intended for continual use. The main advantage would be that there's no need to truck bottles around, and never running out of O2.

[canuckamuck]

And a great piece of mechanical filtration no doubt. Applicable to where I live? What with the maintenance capabilities being a hammer and a screwdriver and the mentality of if it don't fit, force it, if you can't force it f'ck it. Oh,well it was old anyway.

I am more into biological filtration and locally available materials and parts. The automatic cleaning of my old piece of crap design is called a hose. The replacement filter is made in the back yard and the old stuff goes straight into the compost bin.

So far all of my tanks are filtered biologically, with home made filters, however, if you want to go for high densities you are going to need some good mechanical filtration. The biological advantage of the drum filter is you get all the waste to use for whatever you like. I plan to use it for hydroponics.

However there is a nagging voice in my head asking me why I don't try a bog full of shrimp for a filter.

[harrry]

i just took delivery of my drum filter ex china ..good for 30,000 litres an hour, made from marine grade stainless and polymer , if u put both your descriptions together then u have the workings of the drum filter , i looked at making one, but for 130,000 baht landed it was not worthwhile imo ,,,,,as for o2 i think bottles work out cheaper ,,,,,

I would love to hear a review of your drum filter. How many watts does it consume? Does it use UV? Do you like it?

I am still in the planning stages so I won't be buying anything soon, but I might pm you some day for the details of how you ordered it.

About O2, A 6 cubic meter bottle costs about 100 baht to fill, so I wonder if the Oxygen concentration can make 6000 liters for that price. I have my doubts, I also doubt they are intended for continual use. The main advantage would be that there's no need to truck bottles around, and never running out of O2.

6000/60 = 100 hrs. with 1 litre/min

20hours with 5 (say 1 day a bottle.)

capital cost say 3 years to be conservative....concentrator 20000/3 about7000/365 = say 20 baht a day.

running cost I estimate it costs me in electricity for my constant oxygen about 500 a month. 20 baht a day

total daily cost for concentrator 40 baht a day delivered.

total daily cost for tanks about (2tanks about 5000baht capital ) 5 bahts a day capital

gas cost 1 day 100baht

delivery cost unknown needed daily

total cost 105 baht day + delivery

difference concentrator is about 80 baht a day cheaper.

calculations deliberately rounded

They are rated for continuous use as they are for life support and are supplied to Oxygen dependant patients in most countries. My main unit went 3years before failure. I bought another one to act as a spare while waiting for repair (one week) but went back to using the original unit and have used it for another 2 years.,

[Pacificperson]

One thing to think about is that the more densely you pack your fish in a tank, the shorter the time that you have to fix a problem if something goes wrong. There is a limited amount of oxygen stored in a tank of water and more fish use it up quicker. Do you really want to be in a situation where your fish will start to die in less than an hour or two if you cannot fix the problem?

Lower densities give you peace of mind and the ability to sleep through the night without alarms going off.

[h90]

Cheapest way of supplying oxygen would be an Oxygen concentrator. Available here for 20000baht (chinese made but good) They consume round 200 watt on average and supply 2 lpm at about 95% or 4 litres about 90%

That is very interesting, I have never heard of an oxygen concentrator. You have given me something new to research.

I don't know this device, but for scuba diving there is a kind of "Filter" that increase O2 to something like 40-45 % by let O2 easier or harder (can't recall) in than N2.

[harrry]

Cheapest way of supplying oxygen would be an Oxygen concentrator. Available here for 20000baht (chinese made but good) They consume round 200 watt on average and supply 2 lpm at about 95% or 4 litres about 90%

That is very interesting, I have never heard of an oxygen concentrator. You have given me something new to research.

I don't know this device, but for scuba diving there is a kind of "Filter" that increase O2 to something like 40-45 % by let O2 easier or harder (can't recall) in than N2.

The wikipaedia articke on oxgen concentrator http://en.wikipedia.org/wiki/Oxygen_concentrator can provide more information. It does also refer to larger oxygen generators being used in aquaculture. If you go that way the cost would be much higher. In a fairly small system where one bottle a day would be suffient a locally available 20000concentrator would in my view be worth a trial

[RedBullHorn]

Hobby pond with 8 ppm.....

It's like testing the HP of a Ferrari or masarati...... Wish i had that luxury.

Debt ridden with the banks.

[cdmtdm]

i just took delivery of my drum filter ex china ..good for 30,000 litres an hour, made from marine grade stainless and polymer , if u put both your descriptions together then u have the workings of the drum filter , i looked at making one, but for 130,000 baht landed it was not worthwhile imo ,,,,,as for o2 i think bottles work out cheaper ,,,,,

I would love to hear a review of your drum filter. How many watts does it consume? Does it use UV? Do you like it?

I am still in the planning stages so I won't be buying anything soon, but I might pm you some day for the details of how you ordered it.

About O2, A 6 cubic meter bottle costs about 100 baht to fill, so I wonder if the Oxygen concentration can make 6000 liters for that price. I have my doubts, I also doubt they are intended for continual use. The main advantage would be that there's no need to truck bottles around, and never running out of O2.

not commissioned yet , will post pics when its running and a review , no UV ,,, it uses 1 small pressure pump and1 small electric motor to drive a hydraulic gear , total around 500watt , the machine cycles on and off as required so not running constantly ,it has sensors in the barrel to activate its operation ..the water flows thru using gravity ...my idea for the O2 is to use the bottles as a topup when the DO levels drop below my desired level, i will fit an O2 sensor in each tank to control it via solenoids. During normal operation i will have airpumps in each tank using venturis to deliver in the water stream , when a power out occurs the O2 bottles will kick in to ensure the O2 is stable ( waterflow is no concern for short periods due to using the drum filter , only the O2 is critical... so the bottle useage will be minimal , but time will tell if it works ok ...

[cdmtdm]

And a great piece of mechanical filtration no doubt. Applicable to where I live? What with the maintenance capabilities being a hammer and a screwdriver and the mentality of if it don't fit, force it, if you can't force it f'ck it. Oh,well it was old anyway.

I am more into biological filtration and locally available materials and parts. The automatic cleaning of my old piece of crap design is called a hose. The replacement filter is made in the back yard and the old stuff goes straight into the compost bin.

So far all of my tanks are filtered biologically, with home made filters, however, if you want to go for high densities you are going to need some good mechanical filtration. The biological advantage of the drum filter is you get all the waste to use for whatever you like. I plan to use it for hydroponics.

However there is a nagging voice in my head asking me why I don't try a bog full of shrimp for a filter.

i have setup a septic type system using three 1600 litre tanks underground , these are to store the waste from the fish and allow the nitrifying process to occur , this water will not return to the fish , it will cycle thru the nft and grow tower system plus some wicking beds back to the tanks , on timer twice per day ....i think i will put shrimp in my bio to consume anything the drum filter misses ...

[canuckamuck]

One thing to think about is that the more densely you pack your fish in a tank, the shorter the time that you have to fix a problem if something goes wrong. There is a limited amount of oxygen stored in a tank of water and more fish use it up quicker. Do you really want to be in a situation where your fish will start to die in less than an hour or two if you cannot fix the problem?

Lower densities give you peace of mind and the ability to sleep through the night without alarms going off.

This is definitely a big consideration for me. We don't get a lot of power outages but sometimes we are out for a couple of days. My current fish depend on the O2 brought in from my filtration. But I also have the luxury of having river water available from a gravity fed pipe. If the power quits I can keep them alive for a couple of days with fresh water.

I would not be able to do this for higher densities of fish though so If I do go for an O2 system, I will have to have my backup system figured out as well. One thing I will be doing is changing the fresh water pipe from 1.5 inch to 3 (I still have 300 meters of pipe to swap out).

I have to work out my stocking densities so that fresh water plus filtration would get me through a day without O2. However, if I lose two out of three systems. It would be serious.

[cdmtdm]

And a great piece of mechanical filtration no doubt. Applicable to where I live? What with the maintenance capabilities being a hammer and a screwdriver and the mentality of if it don't fit, force it, if you can't force it f'ck it. Oh,well it was old anyway.

I am more into biological filtration and locally available materials and parts. The automatic cleaning of my old piece of crap design is called a hose. The replacement filter is made in the back yard and the old stuff goes straight into the compost bin.

i have done the hours and hours of cleaning filters manually, it does not appeal anymore, on a big system the drum filter is very cost efficient imo as opposed to larger solids and bio filters , plus the hours of cleaning and filter changes ..each to their own ..

[IsaanAussie]

And a great piece of mechanical filtration no doubt. Applicable to where I live? What with the maintenance capabilities being a hammer and a screwdriver and the mentality of if it don't fit, force it, if you can't force it f'ck it. Oh,well it was old anyway.

I am more into biological filtration and locally available materials and parts. The automatic cleaning of my old piece of crap design is called a hose. The replacement filter is made in the back yard and the old stuff goes straight into the compost bin.

i have done the hours and hours of cleaning filters manually, it does not appeal anymore, on a big system the drum filter is very cost efficient imo as opposed to larger solids and bio filters , plus the hours of cleaning and filter changes ..each to their own ..

This is a basic choice we must make. I am limited in choice by limited funds. But having said that, to me the choice is largely who is going to operate and service the more efficient but more complex equipment? I suppose either way we will always remain a slave to whatever system we use.

One issue of importance to me is the used materials and the filtrates produced. The biochar and the biology and fish wastes are key ingredients in my composting and not just spent materials. Dead fish are even an asset as they are fermented into fish hydrolysate which is a great nitrogen source.

As you say, each to their own.

[wolfrunes]

@IsaanAussie

Your setup sounds interesting. Do you mind sharing more with me via pm?

[IsaanAussie]

@IsaanAussie

Your setup sounds interesting. Do you mind sharing more with me via pm?

WR

Which part of my setup would you like to know about? If it is fish the only current involvement is our pond which is currently a main source of algae for fertilisers and food for a "pet" group of maybe 7 year old catfish that fend for themselves. "Warning swim at your own risk" size catfish.

Glad to help with any questions I can answer, but fish expert I am not, yet!

[cdmtdm]

And a great piece of mechanical filtration no doubt. Applicable to where I live? What with the maintenance capabilities being a hammer and a screwdriver and the mentality of if it don't fit, force it, if you can't force it f'ck it. Oh,well it was old anyway.

I am more into biological filtration and locally available materials and parts. The automatic cleaning of my old piece of crap design is called a hose. The replacement filter is made in the back yard and the old stuff goes straight into the compost bin.

i have done the hours and hours of cleaning filters manually, it does not appeal anymore, on a big system the drum filter is very cost efficient imo as opposed to larger solids and bio filters , plus the hours of cleaning and filter changes ..each to their own ..

This is a basic choice we must make. I am limited in choice by limited funds. But having said that, to me the choice is largely who is going to operate and service the more efficient but more complex equipment? I suppose either way we will always remain a slave to whatever system we use.

One issue of importance to me is the used materials and the filtrates produced. The biochar and the biology and fish wastes are key ingredients in my composting and not just spent materials. Dead fish are even an asset as they are fermented into fish hydrolysate which is a great nitrogen source.

As you say, each to their own.

time will tell if it has been a good investment, the equipment itself is very basic in its structure and electrical control , once in place i will break it down into pics to show how it really works ...i agree the waste is also very important for me as well and every bit will be used well in the grow beds ....

[wolfrunes]

Looking forward to the pics

@issanAussie

Interested in the whole setup you have and you mentioned compost..? For growing mushrooms or??

[IsaanAussie]

Looking forward to the pics

@issanAussie

Interested in the whole setup you have and you mentioned compost..? For growing mushrooms or??

I wont ask you to search through all my posts, but most of if is within this site. Nor do I have the time to lay it all out here. One day maybe an E Book, who knows.

For now compost. Yes I produce pig manure based compost. That is used on-farm and is sold. On-farm uses include soil improvement, feeding the worm farm, and producing potting media and the casing material for mushrooms. We also enrich the compost with minerals and pelletise it as fertiliser (just put a ton on my rice crop).

The composting system is a 3 box one where the raw materials are mixed and go through the thermophillic stage in box 1, are moved into box 2 and further additives added during the finishing stage. The final box really is storage pre-bagging. During stages 2 and 3 the moisture level is held above 40% to maximise the biology. After bagging it drys down to about 15 to 20%. I use a lactic acid bacteria to accelerate decomposition and mineralisation, carbonised rice hulls to limit nitrogen loss, and blue green algae to add nitrogen and cyanobacteria (nitrogen fixing bacteria).

QED