Backyard Aquaponics
A place to discuss aquaponics

So to get liquid from mt you need to filter out the solids before you add them back to the Ap system.

The low DO readings are telling me that your growbed is going close to anaerobic. You need a higher clow through the media bed to prevent DO from dropping.. (i think, not sure but thats what I would do) same for netting tank and shade cloth tank. When,do is dropping like that there is a problem.

Thanks for your input.

So how do you know when to add the mt water back into the system? Any recommendations on filtering the water on the way back to system?

After about 24-48 hours of proper aerobic digestion. Through any means of filtering out solids. You have to find what works for you in your setup. I am still struggling with that one. :/

Air, air and more air!!! I agree with Swede about the DO in the grow bed and needing to aerate both the tanks as well. You may find that with the increased flow the DO goes up but hasn't gotten there yet.

What's with the DO in fish tank 1 (1.5 ) . Are there actually fish in that tank, they should be gasping if they are even alive?

I was wondering about that fish tank but assumed it didnt have any fish in it

There must be some 200 fish (one day I'll count them one by one) in in FT 1. During the tank moves and put all the fish in one tank to empty one tank to move it. Then move all the fish to the newly located tank and I haven't split them up yet. Tilapia seem happy really!. Yesterday the DO in that tank was 0.2!!!!!! yea...It was late at night and I couldn't do much more at that point. No tilapia deaths. All the Gold fish died. About six. Today I moved over some of the fish to the 2nd tank but maybe 15 or so. They are hard to catch with a full tank. I need to plumb the IBC bottom drain to the sump still. Fed the tilapia today for the first time in 3 days and they crashed the surface as usual. They are like perannas, it's crazy. Fed them 40 grams today just to help them through the system updates.

I agree, I need more aeration. I'd like to add venturies to the fish tank inlets.

Any idea how to size venturies? Is it by flow or just by pipe size?

I also need to make a home for the air pump then run PVC pipe to distribute the air to the different parts of the system.

lots to do and not enough time.

thanks

200 fish in one IBC? What is the approximate weight of the fish? You will kill more fish at that stocking density. Aim for 1 fish per 5-10 gallons of water unless you know 100% what you are doing. Meaning flow, DO, filtration etc..

I have no idea of their weight. But they range in size from 4-8 inches. Once I plumb the bottom tank drains to the sump, i'll get an accurate count.

Too many fish in one tank. DO for healthy fish should be a minumum of 5mg/L. Maybe your DO meter isnt calibrated correctly?

Calibrated yesterday. FT 1 had maybe 10-15 fish and its DO is much higher. Sump even higher with the 5 air stones. I recalibrate again before the next DO check.

Latest Video update.

https://www.youtube.com/watch?v=U7sYVvFqak4

Again, I agree with Swede (too many fish) but boy those Tilapia are tough. Didn't look like you have quite as many as you thought but they are pretty good sized.

For the flow - Have you considered having a second set of filters. Right now you have two 2" SLO's going into a single 2" pipe that heads for the net tank - seems like this might be one potential bottleneck.

on the inlet into the fish tanks you might get a bit more aeration by pointing the inlets toward the surface of the water or attaching a spray bar. A venturi will also work but I'm not sure what to tell you on sizing and design.

You could also push some of the excess flow from the pump out to the media bed from the sump since that should be pretty clean water.

Yeah, I have to count them one day. Your not kidding on the toughness of tilapia. Love them!




I agree. If the DO does not improve at the GB drain, I will diffinetly consider upping the pipe going into the first filter (net tank) to a 3". Then continue 3" until it tees off to the 2 grow beds.



Tried a 3/4" spray bar this morning. Didn't agitate the surface at all. The pressure was too low. I can probably do a video of that so you can see what I"m saying. Not sure if a venturi will work since it seemed the pressure was low with a spray bar.



I'll up the pipe sizing before I do that. That would be a LAST ditch effort.


Thanks for the input.

I want to install a PVC airline today to supply air to the two filter tanks. Is one inch pipe a good size or should I go bigger smaller?

I'm using a "Elemental O2 Commercial Air Pump" from Allied Aqua 1744 gph.

thanks

Whats the outlet diameter from air pump? I remove the nipple in mine and attach a hose over the actual pump body. Been using 1/2" pipe but a smaller pump