mellow1

The women all seem to be in the same price range, except for aitch52 whose location seems to command a higher price.

My wife has a small fish farm operation. It's a new enterprise for her, and she has a bunch of Pla Duk which have reached market size. The fish range from 4-6 fish per Kilo. They are healthy and look nice, they also taste good. Although BBQ is not my favorite way of eating fish. It seems to me that people are trying to get the absolute lowest price out of her for the fish, and so far she has stuck to her guns. 45 Baht retail and 40 Baht wholesale. I am trying to stay out of it, but I did tell her to just sell to everyone for 40 Baht. In town they sell for 50Baht at the market.

I keep enough for the visa requirements, and haven't thought about it in the past. Our bank account is a joint account with my (Thai) wife,

I did not know that was possible....I always thought the account to satisfy visa's had to be in the expats name alone.

I would think if a joint account is in fact allowed you have no worries

After last years Visa renewal I was told By Thai Immigration that this year, when renewing My visa I would need an account in my name only. I will of course comply with this, but maybe it has something to do with the disclosure laws. As I said previously, I am not into evading taxes, or breaking any other laws for that matter. I'm a US citizen, and never would I want to change that status. This is all due to a lack of interest in such matters, and my fault of course. But a 10,000 dollar fine would really put the hurt on us, for quite some time.

Although I remember this topic being discussed last year, I really never give it much attention. Being an expat on a modest pension somehow made me feel that it didn't apply to me. I keep enough for the visa requirements, and haven't thought about it in the past. Our bank account is a joint account with my (Thai) wife, and I'm hoping that the Thais don't report their citizens account info to another country. This is not an effort to avoid taxes, since I doubt the amount would increase what I have to pay. I hate doing taxes, and more paperwork is even more unwelcome. Having screwed up on the amnesty deadline (which I didn't know about) I would have to do taxes going 6 years back. I don't even want bad dreams that bad. Maybe closing the current account and starting a new one will keep me under the radar, and I can come clean next year by declaring the new account. Do the Thais even have such an information disclosure agreement with the US? Are the Banks here required to do this extra paperwork?

Cheers RBH, wife has been doing a 70% change every 3-4 days and puts in a few handfulls of salt. It is a good point mellow and has been at the back of my mind too, haven't scrubbed the Schmutzedecke either it's a sort of emerald green rather than the light green of algae. The reason we did a 100% change is that we were without water for 4 days, the pumping station broke down.

Those are some pretty good water changes, how did you decide on that amount? Where your fish ready for Sonkran? Are the sales going alright for you?

Just a quick update on what is happening in our tiny operation.

As I am away working during the week I don't get to supervise what is happening. Anyway the first batch have been on the go for 4 months now and probably only 2 thirds of their target weight.

We did a 100% water change at the weekend, mottled grey in colour with white stomachs and look very healthy, which the Boss was happy about. Sizes of the fish vary considerably though, probably 120 to 220 grams. I have discussed the feeding regime with my wife, I think it should be 3-4 times per day but as the lady at the hatchery said twice a day that is what she is doing. After the first two minute or so voracious feeding, much like pirhana, I keep throwing smaller amounts in, broadcasting over the entire surface of the pond probably for 4-5 minutes while the fish are actively feeding.

I think as the fish are now bigger then the growth will be more rapid and they will eat ever greater amounts of feed, The first batch should be ready for Songkran, which will be 150 days .

A couple of questions, as we have missed the 90 day target by a big margin it seems to me the fish haven't been getting enough food for optimum growth. although the second batch seem to be growing quicker. They also seem to feed much quicker than the first batch.

How many grams per thousand fish do you reckon for a normal feed and do you think twice a day is enough, I firmly believe that if you give a large amount in one feed then a good deal of the feed will be converted into sh*t rather than body weight.

Hope your operation is continuing to flourish. I intend to enlarge our operation over the next few months.

Another thing I have noticed is that they seem to love a feed at about 8pm by torchlight, I believe they are nocturnal creatures anyway.

Cheers

Aitch

Wonder what your Nitrite reading is, with one water change per week, and only a handfull of salt in a 3x5 tank holding 2000 fish. I would think it would be off the chart.

My wife needs about 24 AMPs to run this set up and another 20 AMP's to run the water pumps on another set up. That's according to a friend of mine whose good at this sort of calculation. Still waiting for the electrician to show, so I can get his input. But learning what I can in the meantime.

Thanks Crossy, good info. You two Gary A, but we don't use an iron buffalo around here.

My wife's first recirculating system is done, apart from a few little things. She needs a generator or two, to run 2 pumps, an air blower, and lights in case of a power failure. We have a 2.5 KW one, but it ain't got the power needed. It will only run one water pump. We live in Issan, out of the ordinary stuff is hard to find. We want to be able to get an idea on prices, and of what's available. We had the electric installed for the system, including a breaker to cut off electric from the main when switching over to the generators. The electrician is coming by, to calculate the size needed to run this equipment. Links to web sites, or phone numbers to legitimate dealers appreciated, as well as advise.

^ Disease is of a great concern to us. Your idea of spraying the food with medication is excellent. Never thought of that, and I would imagine, it would be the only way of treating fish in a closed system like ours. Do you have a link for the types of medicines used for various diseases? I have very little information on this subject.

We were likewise thinking of selling juvenile fish as you are doing, in order to get incoming cash during the long grow out period. Is there a good demand for such stock?, and what do you sell them for per kilo? Do you get a greater demand for pla nin or tap tin? Do you raise both? I have been reading both your comments, as well as maizefarmer's for a couple of years now and I appreciate the info gleaned from both of you, as I imagine others do also. Thanks.

I will try and post some pictures of the system we are trying to finish over the holidays, while we are not busy. This hopefully will give some constructive input which we may be able to apply in the future. It may also help someone else, wanting to do something similar.

^ I know whom you are referring to ozzydom. I believe his user name on this forum was tilapia. His farm is not far from where we are, and we have visited it, a number of times. He was/is involved with investors ( not a small family farm), and the last time I visited him, his fish were diseased. A disease he imported, when he bought the fish, and put them into his system. I believe he also had other problems not related to an aquaculture system,and not any of my business, he was always nice to me. We are small compared to his set up, have no investors or loans to pay off on this. The filtration system is completely different, easily cleanable, without any manual lifting. It can be handled by one person. It was designed to operate this way by me. I did not of course invent any of it, it all comes from information I have been reading about for about a dozen years. We did however build it to meet our personal needs, which is easy maintenance of all the mechanical filters, as well as all aspects of the operation. A one person job. My wife will not be selling her fish to a middleman, she will sell them in the evening at the local market. Yes there is electricity to pay , as well as fish food. But no matter what kind of fish farming operation you have, you will be pumping water somewhere, and possibly aerating. You will most likely be giving supplemental feed at the very least, if not all the feed the fish require. If you have ponds they will need to be drained to harvest, limed, left unproductive for periods of time. These ponds may also need structural maintenance when empty. You will also need 10 to 15 rie of ponds to achieve what will be produced on about a rie here. Either way there will be operating cost. We built two small experimental systems prior to this. We learned quite a lot from this, as well as operating them. One will be kept running as a quarantine for incoming fingerlings, prior to being added to the system, a lesson to be learned at tilapia's expense. I wish I could say it has all been easy going, getting to the point where this system is almost ready to go, but it hasn't. We are lucky in a way that it took a long time to construct, and we paid our way as we went, it would be terrible if one went into debt, and then having to repay while trying to make a go of things. At this point I cannot tell you of any great success rates in any aspect, but I do believe that my wife can make herself a decent living out of it. That is the reason it's being done. I also have no doubt that there will be many things to learn in the future from this, and various aspects will naturally morph. A little luck wont hurt us neither.

A note regards aeration of water - in containers, pools, dams: injecting air into the water (through airstones or whatever) is actually very ineffecient. We all have this impression that an airstone at the bottom of the fish pond/tank, with lots of bubbles pouring forth is doing a good job. The reality is that nearly all of the bubbles will rise to the surface of the pond/tank without any O/CO2 exchange having taken place at all.

O/CO2 exchange in a volume of water nearly all takes place on the surface - the point of lowest surface tension. The key to effective and efficient aeration of a pond/tank is surface agitation. A 1hp motor driving a paddle system on the surface of a volume of water will provide something like 10 to 20 x's more O/CO2 exchange than the same 1hp motor used to drive a compressor to introduce air [through an airstone] at the base of the pond/tank.

Of course a paddle system may not always be practical on the back of a Toyota pickup, but I have seen them used. Placing a section of plastic gutter pipe verticaly in the corner of the tank with the top of the pipe about 1/4" above the water level, and with the airstone located at the base of the gutter pipe so that as the air bubbles rise in the pipe they draw water with them (just as divers use air inducted suction tubes for cleaning out debris on sunken ships), increases the amount of water the bubles come into contact with at the surface and increases the gas exchange efficiency.

Theory and practice are not one and the same thing,bear in mind here that we are talking commercial applications and not glass aquariums.

The stones we use weigh over 1 kg apiece,we run 6 per pond over 4 x 1 rai ponds simultaniously, using a 2.5 hp blower through 2" pipes .

The bubbles do not just rise to the surface ,they erupt ,throwing a geyser of aerated water and bubbles a foot in the air ,the agitated area from each stone covers about 9 sq metres which creates wavelets as it spreads out over the pond .

Paddle aeraters are not practical on smaller earth ponds due to the erosion they can cause.

Venturii effect appliances can be either water pump operated with air being introduced into the stream via back angled induction pipes above water or air operated ,drawing water from below surface for a similar effect.

We have been there and tried both ,but on a 1 rai pond it requires a 3" 5 hp pump to do a job inferior to the effect of 6 large stones using about 1/2 horsepower .

The effect on fish is in an aerated pond is amazing. To economise we run our aerater on two x two hour sequences per night ,(12-2 am & 4-6 am ) the period from midnight is we find the period of lowest available oxygen.

1000 kg liveweight of Pla Nin in an UN-aerated pond are early morning lethargic and oftimes sucking air on the surface ,they will not take food until sunlight or wave action has built up oxygen levels , mortality often occurs during this period and so health and growth of your stock is compromised.

On the other hand , fish in an aerated pond are lively and take food freely at first light, I suppose you could say they are happier,if there is such a thing as a happy Pla Nin.

Not sure where the cut off points are for volume/energy used/efficiency, but a quick read through your notes would seem to backup what I said earlier - that it's all about surface agitation. That is where the gas exchange takes place - on the surface - the issue then is: Can you introduce more air into the water for a given energy consumption by pumping the air down to the bottom of the pond and letting it rise up to cause surface agitation, or can you introduce more air into the water by agitating the surface, whether it be with paddles, with a corkscrew, or whatever else oe decided to use.

Don't know - thats all about equipment design I guess. What airstones do do, is lift water (with the bubbles) from the deeper layers (where the fish are?) to the surface. So whatever paddle system, or corkscrew (or whatever else is used) needs to be able to achieve, is move the water sufficiently to cause deeper layer water to mix with upper layer water, else the water down below is going to stay low in oxygen.

Decomposing organic matter at the bottom of the pond also reduces oxygen content - so removing organic matter on a regular basis would help, but at what cost?

I'm just sharing ideas, I've never really looked into the subject in much detail.

Decomposing organic matter is a problem. We added a second 2" stand pipe in each tank, which has a 1 1/2" pipe inserted into it. It has holes drilled in the bottom of it. When you lift the outer larger pipe, while holding in place the taller, inner smaller pipe with the holes in it, the sludge on the bottom gets sucked out of the system completely, without ever making it to the filters. For sure we wont get all of it, but it should lighten the load on the filters. Either way, you got do water changes, so replacing the muck with clean water is what we are trying to do. Water changes also occur when cleaning out filters.

Besides the blower injecting air into the system, there are also bio filters (trickle towers in this case) where the water also gets aerated. The water leaves these filters and enters a manifold(larger pipe), which has vertical taller open pipes where air also enters into the manifold. The agitation of the water inside this manifold. along with the air, should further aerate the system ( my idea, so time will tell). It is then distributed to the various tanks via 6 lines which, also have vertical open pipes to continue the aeration process. The blower has been purchased for the air stones, which will be in the tanks,and some filters. These are now the final stages of this system, besides organizing and adding media to various filters.

A note regards aeration of water - in containers, pools, dams: injecting air into the water (through airstones or whatever) is actually very ineffecient. We all have this impression that an airstone at the bottom of the fish pond/tank, with lots of bubbles pouring forth is doing a good job. The reality is that nearly all of the bubbles will rise to the surface of the pond/tank without any O/CO2 exchange having taken place at all.

O/CO2 exchange in a volume of water nearly all takes place on the surface - the point of lowest surface tension. The key to effective and efficient aeration of a pond/tank is surface agitation. A 1hp motor driving a paddle system on the surface of a volume of water will provide something like 10 to 20 x's more O/CO2 exchange than the same 1hp motor used to drive a compressor to introduce air [through an airstone] at the base of the pond/tank.

Of course a paddle system may not always be practical on the back of a Toyota pickup, but I have seen them used. Placing a section of plastic gutter pipe verticaly in the corner of the tank with the top of the pipe about 1/4" above the water level, and with the airstone located at the base of the gutter pipe so that as the air bubbles rise in the pipe they draw water with them (just as divers use air inducted suction tubes for cleaning out debris on sunken ships), increases the amount of water the bubles come into contact with at the surface and increases the gas exchange efficiency.

Good idea about the pipe and air diffuser, and therefore creating an airlift type system. Will try it out after I figure out what size blower to get.

Went to the government fish farm yesterday afternoon, to see their aeration set up. The men in the office were real nice and interested in what we are doing. We had been there before, and they were equally friendly, they even ran water tests on our water that first time

Anyways, they showed us their aeration set up for their tanks, and hatchery. Here they used both devices, blower and supercharger. They said that the blower is the way to go, and that the supercharger break's down a lot, and gives them nothing but headaches. They also said the blower is much quieter. We checked out the piping system for the air, and then looked around at other things.

They had a filter system for the tanks and one for the hatcheries. The filter system was minimal, in my opinion, mostly due to very little filtering media. They did however have a nice aspect to it, in that it contained plants. The plants looked healthy from all the nutrient they were getting from the water, but they could of used a few more plants. The water was quite opaque in the large tanks.

All in all, it was a nice and informative tour, and like I said the people where friendly, helpful, and told us to come back anytime. We already made inquiries about blowers after ozzydom's responses to this thread, and it looks like the way to go. Thank you for your replies.

Thanks thaimite, gonna try and replace the cable.

mellow1 , I will try to get a pamphlet from the agent here when I go to town .

There are a couple of sizes of used bus blowers available at the wreckers ,I would go for the bigger one you can find, it will take about a 2.5 motor to spin it.

Get the plainest one available, with a standard crank end to facilitate pulley changes. One I used was a disaster as I bought it sight unseen and it turned out to have a multi splined crank end and an electronic clutch pulley which was nigh on impossible to change ratios.

I have read a little about raising Tilapia in tanks but have never given it a lot of thought.,Have you a cost analysis on this form of growing out, how many fingerlings would you carry to 500gram in each tank?

One of the main problems is the market price available ,which is pretty stable at 70 baht farm gate retail and 60 baht wholesale , With low (16% ) protein food at about 25-30 baht kilo and 25% at up to 40 baht kg an FCR of much over 2;1 it becomes very marginal.

The only data I have seen was from the USA ,where costs are entirely different to here , I imagine retail prices are much higher but with fingerlings advertised at $1 each against the 50 satang here they would need to be.

I even tried value adding by doing skinned boneless fillets,but with !kg fish being the optimum for filleting and only a 30% recovery it meant a break-even price of 250 baht per kg retail price. ( another bright idea down the gurgler)

Thank you for your interest ozzydom, I appreciate any info you can pass along to us.

In each tank ( 1000 liters of water) there will be 100 fish grown out to 500grams. They will be grown out in larger tanks to about 700 grams, at which point she will start selling.

Here(Issan) Tilapia go for 80 to 85 Baht/Kilo. My wife plans to sell them herself at the local market.

The fish will be fed feed which contains 35% protein, she previously used 32%, and the grew well and tasted very good. Tasted much better then pond raised. The feed goes for 470 Baht/20 Kilo. The fish will be sold live to the customer.

With no middle men, she should be able to make a decent profit. Small family operation, with 1 employee, maybe 2 if it goes well.

We are also going to check out the government fish farm around here, to ask about their ideas for aeration.

The blower ,motor, fabrication etc was about 15k ,plus another 10k for the electric timing and overload cutouts,switches etc.

I only found out that the cyclone type with integral motor was available when buying a smaller model for our nursery hapa,s , initial enquiries indicated that a large cyclone blower would have worked out about the same cost without the hassles.

Ours and all the blower setups I have seen are plumbed just like you were plumbing for water,ie. a 2" main line and reduced branch lines for each pond ,each must have a valve / stopcock to control the amount of air to each application ,and of course a valve on the end of your main line to exhaust excess air, the end should be directed under water as exhausted to atmosphere ,they sound like a jumbo jet .

Some applications use pvc piping fitted to the bottom of the pond and just drilled with small holes every foot or so but the smaller bubbling caused by stones is more effective than large bubbles .

A manifold would not accomplish much as each line would still need to be adjustable per valving.

Thanks again ozzydom. I went in to check with to hardware supplier that I use here for various things, and he said he would check into the Cyclone blower for us. My wife has set up 51 tanks, each holding a cubic meter of water. It's a recirculating system for Tilapia. The plan is to raise the fish to 1/2 Kilo in these tanks. The water pumps have been installed, and the system is being fine tuned. She is also arranging media for the filters, and experimenting with spray bars for the Bio filters.

As far as the blowers go, are there any other brand names which you can recommend ( if Cyclone can't be had here), and what size blower would you recommend also.

At 6AM I got 4 bars and a speed of 1.4 Mb/s, 30 minutes later it dropped down to 3 bars, but still got 1.3 Mb/s. Could it be more users coming online affecting the signal strenght also?

The one we have fitted at the farm is a rootes type but is actually the one used on buses to provide air through the air con system. They have a wet sump so lubrication is not a problem, we use a 2.5 hp single phase motor.

I piped ours through 2" pvc piping to 4 ponds and reduce to 1 1/2 " along poles across each pond .

Each pond has 6 x 5" bubbler stones on 1/2 droppers. Each of those ponds is about a Rai each and 6 big stones seems sufficient,

Getting output data was a dead-end so I started out at 1100 rpm and finally settled about 1700 .

There is a bit of fiddling ,making mounting frames and fitting everything, if I were to do it again I would buy a cyclone style blower which can be had from larger fish and aquarium suppliers, they come in a variety of sizes .

Fisheries at Udon Thani have a large one aerating multiple concrete ponds and it has been going for years without problems.

Thanks for the reply. I was thinking that a supercharger might be the economical way to go. Of course it will need an electric motor and a back up generator, but right now its getting the most for the money. That's why I wanted more info on that. Also would like some insight on the set up. I imagine a distribution manifold would be required, in order to distribute the air more evenly. Any links or advise are appreciated.

Thank you all,for your input thus far.

I have the same setup as you, and am 11Km from the tower and get a full 5 bar signal strength.

So although there are boosters available you should check your installation first.

Without the antenna I barely get a 1 bar signal from the Melrin X720 Express card

Some things to check.

• Do you have clear line of site to the transmitter? No houses or steel structures in the way?
  
• How many elements has your antenna (cross pieces (Mine has15 or 16 not sure because the sun is directly overhead and I am unable to check) but the more elements the more gain from the antenna.
  
• In my case these elements are horizontal I assume all transmitters have the same polarisation.
  
• Try rotating the antenna slightly to ensure it is lined up correctly
  
• How long is the cable? A long cable will dramatically reduce the signal strength especially if it is a poor quality cable. (my cable is 10 Metres)
  
• Ideally the cable should be 50 Ohm low loss co-axial. My supplier gave me 75Ohm low loss which I replaced and it improved the signal. If I remember correctly good quality cable will be 200 or 300 Baht a metre
  
• Lastly get somebody to check the connections that the cable has been terminated correctly and that there are no shorts in the cable
  

Hello thaimite, followed your instructions step by step.

1) There is a clear line in the direction of the tower as far as the eye can see, only tree tops, no steel or houses.

2&3) There are 15 elements on the antenna which where originally vertical, but have been changed to horizontal.

4) Rotated the antenna ( slowly) 180 degrees away from desired direction with no signal change, it remained 3 bars.

5) all 15 Meters of cable is needed to reach inside house and PC.

6) the cable supplied with the antenna is : MTV RG-6U 75 Ohm High Performance Cable USA Standard 080M.

7) Cable is in very good condition without any kinks etc.. and brand new.

It would seem that replacing the cable to whatever you got is all that's left to do, please specify your cable. Apparently the antenna is getting a signal of 3 bars in whatever direction I turn it.

Speed test shows 0.78Mb/s for download speed, and 0.35 for upload.

Thanks for your input thaimite. I will check all that out tomorrow. The cable came with the antenna from CAT, it was included with the antenna, it's 15 M long. I'm using all of it, and the antenna is 8M above ground with no structures in the way. The rest will have to wait till daylight.

Got us a CAT CDMA directional antenna which hooks into a Merlin X720 Modem EV-DO REV A 3.1 Mbts. Signal indicator only shows 3 bars full out of 5. Sometimes the 4th bar also lights up. We are only about 6 Kilo from the tower and we are getting about 5-7 hundred kbts/s. Is there a antenna booster we can get for this?

My wife has set up some fish tanks (cement), to raise some Tilapia. She now needs air going into the tanks. We have seen a Supercharger at a fish farm in the past. We know little about it, except it produces a lot of air, and are not suppose to be expansive. I read that they are used for supplying air to engine turbos.

Have you used one? How did you set it up? What did it cost? Are there different sizes? Appreciate any help on the subject

If the children are both Thai and US citizens ( born in US), they can get a Thai birth certificate. It's all I need at Thai Immigration. Maybe one day those computers at Immigration, will be actually able to access a database related to the job.

Hi thanks for reply,could u please explain a bit more?

After our son was born, we went to the Thai Embassy ( we were still living in the states at the time), and had a Thai Birth Certficate made for him. They were very, nice and it was easy. I don't know your location, US or Thailand. I would think if you are here in Thailand, you may need to have your child's Birth Certificate translated, then you would have to go to the Amphur. You should go there and ask first maybe. Also, my son always used his US passport when entering the states and vise versa. Never had a problem with it.

If the children are both Thai and US citizens ( born in US), they can get a Thai birth certificate. It's all I need at Thai Immigration. Maybe one day those computers at Immigration, will be actually able to access a database related to the job.