Pond Boss
Posted By: Cecil Baird1 Small Scale DIY RAS 2.0 The Tank Part 2 - 02/07/16 09:45 PM
Although commercial aquaculture tanks are usually made of fiberglass and other materials, the prices are usually out of the range of the small scale DIYer, and that includes myself. Sometimes the shipping is nearly as much as the tank!

I prefer plastic stock tanks that I can get either from a farm supply or other big box store, or fortunately for me, I have a plastic tank manufacturer within a reasonable driving distance that sells me tanks that have minor flaws for about $100.00 for a 4 to 6 foot diameter circular tank. I prefer circular tanks for properties that will be covered later.

Here is a 7-8 foot plastic stock tank I use for my summer outside system and a holding tank, when seining the big trophy pond. Will not fit through a normal doorway!


Here is one of the plastic tanks I purchased off of the plastic tank manufacturer. They are actually initially much taller but they will cut them down to whatever height I prefer.


Do not use a galvanized stock tank for fish like this one unless you coat it with a fish safe pant like the one below.







Even then, you are better off getting a plastic tank that will probably be cheaper than buying and then painting a galvanized tank, (The paint isn't cheap). At some point the paint will peel up somewhere in the tank. When it does that, it's only a matter of time before water works it's way under the paint and the paint and tank progressively deteriorates. I was given two galvanized tanks and have since given them away.

Intex swimming pools like the one below, that range from 10 feet to 24 feet diameter are another option. Very cheap! A 10 foot pool can be just over $100.00 including free shipping. Many times local big box stores like Walmart, K-mart or Sears even carry them.

You can either raise them on 6 by 6 posts lying on the ground or floor with plywood as a base to elevate the tank to install a center drain, or you can trench in a drain in the ground and install a drain through the bottom of the pool similar to a liner which folks do routinely with koi pond. The remainder of the trench can be filled in with soil or sealed with concrete.

Too be safe for fish use you should wash down the insides of an Intex pool with a dish detergent soap solution, and then rinse. Then fill with water and let stand a few days and rinse again. There may be plasticizers present that could be harmful to the fish.

I know shrimp growers that have used these for years with no issues indoors.

Posted By: Bill D. Re: Small Scale DIY RAS 2.0 The Tank - 02/07/16 11:44 PM
Great stuff Cecil! I, for one, really appreciate you taking the time to pull this thread together. I'm looking forward to reading more! smile
Posted By: Bob-O Re: Small Scale DIY RAS 2.0 The Tank - 02/08/16 12:01 AM
Cecil, sorry ta have asked about your original post about DIY RAS.
Actually I'm not. Seems like with this post you have started one that will get lots of attention and probably get quite a few folks started on a journey that will be very rewarding.
Thanks again for all that you contribute.
Keep on keepin on!!!
Posted By: Bill Cody Re: Small Scale DIY RAS 2.0 The Tank - 02/09/16 09:35 PM
These methods can be downsized and then be used for small tanks if space is limited or a small RAS is desired. Several small tanks could be connected in series with one large community filter for raising or isolating different species.
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/10/16 03:25 PM
Absolutely!

An aquarium is in reality a very small recirculating system that is set up for easy viewing.
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/10/16 11:42 PM
Any numbers on optimum flow rate, circular motion like in rpm or feet per minute measured from a fixed radius for best results?
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 12:17 AM
Originally Posted By: JKB
Any numbers on optimum flow rate, circular motion like in rpm or feet per minute measured from a fixed radius for best results?


What'd think I am an engineer or somethin'? grin

15 to 30 cm. per second for optimal bottom cleaning.

0.5 to 2.0 times the fish's body length per second for best fish health.


http://ag.arizona.edu/azaqua/ista/ISTA7/...nk%20Design.pdf

All the same stuff in Timmon's and Ebeling's latest recirculating book. (The green one).
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 12:34 AM
Originally Posted By: Cecil Baird1
Originally Posted By: JKB
Any numbers on optimum flow rate, circular motion like in rpm or feet per minute measured from a fixed radius for best results?


What'd think I am an engineer or somethin'? grin

15 to 30 cm. per second for optimal bottom cleaning.

0.5 to 2.0 times the fish's body length per second for best fish health.


http://ag.arizona.edu/azaqua/ista/ISTA7/...nk%20Design.pdf

All the same stuff in Timmon's and Ebeling's latest recirculating book. (The green one).


I have the yellow book, that I don't know where it is at the moment.

Both those guy's use my media from Denmark. I bought it from AST where Ebeling is associated with. Didn't know that till after the fact tho.

Also, tried to find the green book, but why would they change colors, as it was well known as the "Yellow Book".

My memory may still work at times laugh wink
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 12:45 AM
The book I have is lime green. (But maybe considered yellow?) Recirculating Aquaculture 2nd. edition. Has a tilapia and half a crayfish and Q1 C2 - Q1 C1= Px on the cover. Got it for a song from one of his attendees of his class that he charges an arm and a leg for. I think it was over their head. LOL
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 01:27 AM
Looks like there may be two 2nd editions out. One is green and one is yellow. I bought mine directly from Cornell about 12 years ago. There is a 3rd edition out, but why waste the money.

Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 01:35 AM
Originally Posted By: JKB
Looks like there may be two 2nd editions out. One is green and one is yellow. I bought mine directly from Cornell about 12 years ago. There is a 3rd edition out, but why waste the money.



It's probably the same stuff rehashed or really big high priced systems. 80 percent failure rate of commercial RAS businesses. To much initial capital to recoup and poor business plans. Bell may be sold by the 19th. Probably some foreign investor. 100 million dollars invested in Bell! shocked

Btw had farm raised steelhead fillets for lunch today from Washington state today. Really really yummy!
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 02:03 AM
Originally Posted By: Cecil Baird1
15 to 30 cm. per second for optimal bottom cleaning.


Measured where?

We are talking about a radius here dealing with velocity?

I mean, where do you pinpoint this at?

Come on, this is a DIY thread and those numbers don't mean anything without nailing down specifics like at least where you measure this velocity at, and doubt many would buy a book that has crazy math in it.

This will all change quite a bit depending on tank diameter and water depth, so some insight would be nice on a DIY rig.

I mentioned that I may have a few questions.
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 03:56 AM


Originally Posted By: Cecil Baird1
15 to 30 cm. per second for optimal bottom cleaning.


Originally Posted By: JKB
Measured where?


In the water of the tank. grin

Originally Posted By: JKB
We are talking about a radius here dealing with velocity?


Huh? What's radius? grin

Originally Posted By: JKB
I mean, where do you pinpoint this at?


I didn't. That's what the book says. wink

Originally Posted By: JKB
Come on, this is a DIY thread and those numbers don't mean anything without nailing down specifics like at least where you measure this velocity at, and doubt many would buy a book that has crazy math in it.

This will all change quite a bit depending on tank diameter and water depth, so some insight would be nice on a DIY rig.

I mentioned that I may have a few questions.


Seriously though those aren't my numbers as you know, But you asked if I knew of any numbers so I got them for you. grin I just know I adjust the flow from my vertical and horizontal spray bar until the fish can't swim a against it or they would prefer to drift back. Then I back off the flow.

And I've actually purposely pinched a pellet and watched it sink and then move toward the center drain in a tighter and tighter circle. And of course there are plenty of solids when I pull the knife gate valve twice a day.

As I've said I'm smart enough to be an engineer but I can build what's needed and solve problems. The fish I've raised in these systems grow rapidly and are healthy. I've got SOME bluegill now that are 4 months away from being a year old and are already 8 inches. I'm hoping I can grow a few 1 lb. bluegill in a year like Lincoln University. That would be cool!

Anyway just want to share this with others to use as a tool for their ponds.
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 04:15 AM
So, basically going by the seat of your pants and what seems to work after trial and error.

Sometimes that works well.
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 04:12 PM
I prefer the words "trial and error" guided by research, and cut down to my application, but that's pretty much it in a nutshell. wink

Hey if you can get some grant money funneled my way I could get really detailed! grin
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 06:19 PM
Originally Posted By: Cecil Baird1
Hey if you can get some grant money funneled my way I could get really detailed! grin


You ever notice who gets the NCRAC grant money?
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 06:32 PM
I've been out of it for a while. Who's getting it now?
Posted By: JKB Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 08:44 PM
The same people who have always been getting it. Like a tiny little club with a secret hand shake.

Maybe you should apply to be part of a research project. Nothing to loose.
Posted By: Cecil Baird1 Re: Small Scale DIY RAS 2.0 The Tank - 02/11/16 09:32 PM
Originally Posted By: JKB
The same people who have always been getting it. Like a tiny little club with a secret hand shake.


But who are they? What state or University? I want names! grin


Originally Posted By: JKB
Maybe you should apply to be part of a research project. Nothing to loose.


Naah don't want any government money. I don't want to be beholden to them or have them snooping around. smirk
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