PLJ's Big Concrete Tank System

PLJ

G'day, Aquamullet! Thanks for your comment, and for honouring me with your first post.

I look forward to seeing your system once you create a member's system thread. :wink:

Cheers,
Peter

Mel Redcap

If you've got a waterproof camera (or a waterproof housing for one), you could stick it on the end of a long pole or string and wave it around the bottom to have a look. It would be interesting!

(I'm having way too much fun with my new little camera. :lol:

)

DomArnett

Nope, just got done reading all 47 pages, and his water has too many tannins for camera work. Awesome setup though. Do you get sick of eating trout all the time? I have been researching AP for a couple of weeks and was sure I wanted to raise tilapia even though I would have to build a greenhouse and heat the water. Then I came across your system thread. I've fished rainbow trout out of local streams my whole life, so I should have thought of them myself, but I must have had the blinkers on as you say. Lol

PLJ

G'day, DomArnett.

Mel, our friend from Snohomish County, WA. USA is right; the visibility is quite low due to the presence of tannins. The depth of the water and the dark walls of the tank don't help much with visibility, either! A few years ago when a friend donned a wetsuit, goggles and snorkel before descending to the bottom of the tank with a bright underwater light in hand, she reported that she could barely see her hand in front of her face, even using the torch!

I would hate to get sick of eating trout so rarely eat more than two per week. I grow many more than I could personally consume but, naturally, have many appreciative family members and neighbours. Additionally, I sell fish.

I haven't grown tilapia but can attest to how enjoyable, and often how exciting, it is growing one's own rainbow trout. Good luck with it, DomArnett.

DomArnett

Thank you PLJ, I certainly will. Right now my wife and I are looking for a house with some property a little farther inland to the East of us. Where we are now sees 200+ days of rain a year and seems to get wetter with each year. We want to move into the rain shadow on the other side of the Cascade mountains. I will probably start my own thread anyway though so I can get input from the planning stage on. There is a lot of knowledge here in these forums and people who have already made the mistakes I'm likely to make left to my own devices.

Mel Redcap

Aw, darn! Forgot about that.

rininger85

Sounds like diving in our local lakes, it's exciting not knowing what you'll bump in to when you can't see past your nose =)

Part of my master scuba diver course was practicing "blind diving" like that... they actually put a neoprene insert in our mask so we couldn't see anything then had to practice navigating around a roped off course and staying neutrally buoyant while not being able to see what you are doing... it was good fun until I hit my head on a metal pole of our "training platform" in the lake... the instructor got a good laugh out of it at least.

PLJ

Rininger85, that sounds like it would be excellent underwater caving preparation - for anyone crazy enough to pursue such a pastime!

rininger85

PLJ wrote:

Rininger85, that sounds like it would be excellent underwater caving preparation - for anyone crazy enough to pursue such a pastime!

I've dove in one cave/cavern... King's Cavern in Crystal River, Florida. It was a bit spooky at first, it was several years ago so I didn't have nearly as much diving experience as I have now. I had never done a true "night dive" at that point where you are diving in pure darkness other than your lights... we swam down through this crystal clear water and go through a little opening in the rocks which opened up to a big antechamber but it was pitch black... first time using a dive light I got a little dizzy because you couldn't tell what direction was up until I got to a wall so I had something to look at and could watch my bubbles go up. There were several chambers that we were allowed to explore and one chamber we were not allowed in because the dive master said if someone had bad buoyancy it is a silt bottom in that room and it will cloud up in seconds and not be able to find your way out. It was kind of neat to see some of the small areas where fish were calling home. I saw a little blue crab in there that was super aggressive wanting to attack me when I was trying to take a picture of it. Now I've done a number of true night dives where the only light available is your dive light, so I'd like to go do some more cave/cavern diving now that I'm more comfortable diving in general.

PLJ

I drained the big fish tank last week in order to catch the resident silver perch, but also to give it a clean prior to homing my next batch of trout fingerlings/yearlings. I was pleasantly surprised at the lack of sludge and general detritus on the floor of the tank.
The image depicts the dirtiest section of the tank. Interestingly, and contrary to what I was expecting, the areas where there were small amounts of sludge were along the pipes themselves, rather than between them. This indicates, I believe, that there is adequate water movement to move any waste that falls to the floor across the bottom until it is stopped by a drain pipe. At this stage it will most likely be sucked through a drain hole, but not always.

PLJ

Here's another view. It's quite clean, considering the amounts of commercial fish feed and insects that have been fed to the 600+ fish that have called the tank home since this time last year!

As well as the remaining 35 or so silver perch that I caught with the tank drained, I found a barramundi - the sole survivor of 80 barra fingerlings released into the tank at the start of what was an unusually cool summer.
The little fella has pride of place in my large goldfish aquarium which, for the first time, contains a heater.

boss

It's a wonderful feeling to see a system working perfectly as planned.

Bender

Love your work PLJ

Sent from my iPhone using Tapatalk

Petesake

PLJ Wrote: This indicates, I believe, that there is adequate water movement to move any waste that falls to the floor across the bottom until it is stopped by a drain pipe. At this stage it will most likely be sucked through a drain hole, but not always.

I reckon when the fish swish around at the bottom they send the muck flying around until it gets caught in a flow stream and sucked in one of the holes and as it appears a small amount gets caught in the flow-less corner between the pipe and floor. Maybe raising the pipes just 1/4" would allow muck to be swished around until all is gone.

PLJ

Thanks for your supportive comments, Boss and Bender.

I should have thought of doing as you suggest, Petesake, since when cleaning the tank I actually lifted the drain pipes a little as I swept to allow waste to wash under them with the swept water. The improvement to floor-flow would be simple enough to achieve, too, but will go on the list for next season's improvements since the tank has been cleaned and now has 90,000L of ancient brown groundwater in it.

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