Pond Boss Forums INTRO Questions & Observations Current in a RAS

I have 250 LMB in a RAS they are very fat. If I add current to the system would that help trim them up, without slowing down there growth?

It may not trim them up but it would promote their health. I think backing off on the feed a little would help.

Is your tank circular or rectangular? If it's circular and you have a center drain you could kill two birds with one stone by creating a centripetal flow (teacup effect). That is the circular current would direct solids to the center drain.

Im not sure if you checked out the pictures in my post below of my flow thru tank system that I am keeping my Brookies in. At the start I was pumping just 1.5-2 gallons of straight well water into the system (700 gallon tank)and I didn't have as much of a swirl as I had wanted. I have tweaked the system a few times in the last 3 weeks and am now pumping 4-5gpm out of the tank via a jet pump and preasure tank up thru the degasser unit and back down into the tank inflow port. With the new almost 7gpm of inflow into the tank there is a very noticable swril and current in the tank and all the trout are facing the inlet and swimming constantly counter clockwise (flow in the tank is clockwise). The seem happy and healty but I would think that could be a bit much flow for your system as bass don't really need as much current.

Ryan

My tank is circular. It is a 30' above ground pool. It holds about 20,000 gallons. My pump is running at 100 gpm. How much speed do I need to shoot for?

Also does a fat bass put on length faster than one that is closer to the standard for rw?

Wow that's a big tank! And 100 gph is quite a bit. Can you direct it tangentially toward the outside edge of the pool to get a circular flow going? If the flow is too strong adjust the direction of the inflow down more than sideways.

Your fat bass are well fed bass and will put on length as fast as possible.

What do you use for a mechanical filter and a biofilter? How much water are you reusing?

Ryan,

What was the diameter of your tank, how many trout to you have in there and what size again?

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Ryan,

What was the diameter of your tank, how many trout to you have in there and what size again? [/quote]

its an 8' dia with 24" of water and is aprox 700gallons give or take a few. I am actually thinking of dropping the water down 2" so I can have the water inlet above the water shooting out the 1" PVC. I have done alot of experimenting and my best full swirl is happening when I drop the water down just below the inlet. I just added the pressure tank to the setup the other day and its great on the hydro bill (pump runs for 1 minute 15 seconds and then shuts off for almost 3 minutes) and I have the same gpm heading up to the degasser as I did before. I just might add another and even larger presure tank so I can get even more circulation!
I have aprox 25 brookies, 2 rainbows and 2 browns in the tank currently at legths from 18-21" and in the 3 weeks they have really started to put on the weight and inches. I am still constantly running well water also and have 1.5 gallons flowing thru and everything is seeming to do great.
Also, the little trick my pond guy told me about with the lower drain just before the gate valve and the 1/4" hose pulling the solids towards the valve is working great. I have a gallon pail out in the bush where the water exits the system and if I dump it out and go back in and give the gate valve a quick up and down and go back out and check the pail there is nothing but solids, food scraps and waste in the pail. Here is one picture I took which was from one quick opening of the valve...I am sure there would have been even more if I would have held it open for a little longer.


Last week I was at the largest of our Ministry of Natural Resorces fish hatcheries in northern Ontario (they are the hatchery that saved the Aurora Trout from extiction...if your not familiar with them they are a verson of the Brooke Trout without the speckles http://www.auroratrout.com/ ) Anyway, they are the largest provincially own trout hatchery and specialize in Brookies or Speckled trout as we call them up here. I showed the manager my pictures of my setup and was amazed at the setup as even my degasser unit was a scaled down version of what they have (they have 250 pails of 1.5" bio barrels pumping 5000gpm thru them!!!). He said that inflow will be the most important but I should have no issues with 50lbs of fish per gallon and said I should be able to put at least 150-200lbs of speckles in the tank pumping in 4gpm of well water and recirculating another 4gpm thru the degasser if I wanted to do so.

I am reusing 100% .
As for filtration I have 8 filter mats of graduated size in a box that the water flows through as it leaves the pool then it goes into a 700 gallon animal water tank where I have 30,000 bio balls. It is then picked up and pumped through a 1200 watt viper uv filter. When it renters the pool it goes through a diy foam fractionator.

I know it is a little overkill but I don't want to just get by.

This fish tank stuff is catching on!

Pretty cool how creative everyone is at this and making it work well!

Ryan,

Just keep in mind there comes a point if density is increased enough -- when although the fish seem to live and feed well -- their fin quality starts to degrade. It's not an issue with food fish or even fish and game departments (I think we've all see the ragged fins on raceway trout).

This is something I have to be careful of when I change over to all RAS vs. the earthen pond I have my trout in. If my trout have any flaws the price I can get drops considerably.

I know exactly what you mean Cecil- All of my brookies have raged fins from my supplier but I am not concerned as they are only for eating...now if I was doing what you were doing it would be a huge issue forsure! Are you thinking of doing the trout (Tigers)for there full lives or grow them out in the pond once they are larger?

Does the number of fish in the tank affect the growth as they get bigger? I would think it would with high fish dincitys, but I plan on keeping it to atleast ten gallons per pound of fish. If I had more water per pound would I get better growth later on?

My goal is to see how big I can get them in four years on pellets alone.

Thanks for the help this forum is the best!

My pond supplier who was a major help in giving me ideas for my in door system along with Cecil raised LMB in a RAS for 3 years. He told me that out of all the fish he had ever raised in a tank LMB were by far the hardest. He said that he had to constantly sort them for size and remove the smaller or larger ones on a monthly bussiness. All was well with the system for 2 years but by the time they were pushing 2 lbs they started acting strange and dying. He said that testing was done on some of them and if I remember corectly he stated that it was due to liver issues which probably stemmed from 100% pellet feeding. He was feeding a trout style food though so that may have been the issue...I don't know??? It was pretty neat seeing him raise them the few times I went into the store and had the chance to see them though! Good luck with the setup! You tank/pool sounds huge! Do you have any pictures you can post???

Ryan

If I do tigers I may get the triploid eggs this fall and hatch them out in the basement. If I do that I will keep them inside and put them in a cage in the trout pond the following spring. Otherwise the larger trout in the pond may eat them or not allow them equal access to the feed.

I'd like to build a building to do this but probably won't have the funds for it until the fall of 2014 when I sell my 4 to 6 pound brook males. I should have at least a 100 of them and can get at least $50.00 each so that will be my fund for the building.

On the other hand I may just wait until I have the building.

It's not fish growth you have to worry about with higher fish densities. It's reduced water quality which causes obvious problems. Specifically higher densities reduce oxygen levels and increase ammonia, nitrites, and nitrates. Most fish don't have a problem with nitrates but trout do.

I was told by some experts in growing out salmonids in an RAS, as long as I stay below 0.25 lbs. of trout per gallon I should not have any fin issues. I doubt I'll even get close to 0.25 lbs. per gallon with the trout, as with the price I get for them, I don't need to and to me 0.25 lbs per gallon is a lot of fish.

Hi Cray
I thaught i'd throw in this http://www.nofima.no/en/nyhet/2013/03/salmon-smolt-on-training-camp
the research has been going on since 2008 and the results shows a 10% higer survival rate on the smolt that has been given training/excersise
compared to those that don't.
Less need for medication etc etc.......

cheers

Apparently being sedentary is not good for any organism that is not adapted to it. Makes sense.

There is published info on current flow and fish growth/health, mostly for salmonids. Don't ever recall any info on LMB tho.

Can't remember if it's in a book or been published online. Just have to Google it yourself. Did I ever mention that I hate Google

My bass are fairly uniform at 12-14 " . I have had them for 13 months. When I got them they were 2". I'll get a few pics up as soon as I can.

Cecil did you see any aggression when they got to breeding age?
Also if you can think of anything that I might run into problem wise please let me know.

Pics are always good

I have not raised largemouth bass in an RAS. Smallmouth from fry to about 5 inches yes.

I have grown out largemouth in cages and found them very adaptable to cages if they are feed trained fingerlings. However I released them into the pond by fall (got them in the spring at 4 to 5 inches) and released into the pond when they were 8 to 10 inches. (Large enough to not be an easy meal for the larger largemouth and yellow perch.)

I've been told largemouth reach a plateau at about 1.5 lbs on artificial feed.