Backyard Aquaponics
A place to discuss aquaponics

Hi Mathew,
That pH would be very nice if you could hold it steady. (btw I would start up the pump in the wee hours of the morning. DO is lowest in early morning. Actually, I think I'd run it all the time. Would that be a problem?)

Would you post pics of your unhappy plants, with close-ups of the leaves and specific comments on why you think they are unhappy. Also some overall shots to give a better idea of light exposures, setup etc. It'd be really cool if you put those in your own thread, though. I promise, I'll follow you there. I read most of the activity on the forum every day. I can think of several causes: truly low nitrate, low iron, or low light.

sure Janet,
I was just getting ready to appologize for taking over your thread anyway. As for the photos, I will have to work on it and the amount of light is not limited.

I will put it on the thread that is here http://www.backyardaquaponics.com/forum ... 4692#74692

We had another meal of tilapia last night. The girls loved theirs. Husband still was complaining about having to deal with bones. I even pulled the main skeleton for him. The fish were bigger than I thought -- most of them were 300g, and I fixed 5 of them. So there is leftover fish in the fridge for lunch today. I just fried it again, but really want to do the next meal on the grill (barbie!). So we'll hold off another month for the next meal, and I'll plan on preparing 2-3 fish. Hopefully when they are a little bigger, I can fillet them. I've never done that, but I guess I'll be learning.

with a little luck, you can cut out the dorsal fin and then pull out the main skeleton leaving virtually no bones. I saw a youtube demo about it, I will try to find it and post it.

Any idea how much yours are weighing?

Hi DT,

Biggest are 300g (10-11oz), down to the small end at maybe 200g (7oz). My kitchen scale only goes up to 300g, but as a double-check, I weighed after cleaning, too. (Removed head, gut, fins, scales) After cleaning, the 300g fish was 150g, so I think the 300g was actually about right.

I'm very excited to be within reach of fish weighing a pound. I know tilapia will go up to a kg, and just can't imagine pulling one of those out of the system. Hmmmm....what an awesome Christmas dinner that would be!!

I'd be very interested to see that video if you can find it. Tilapia also have some funny bones--I think they're really the base of the dorsal and anal fins. But they make nasty little splintery bits that I have trouble finding, and I don't want the kids choking on. As the fish get bigger, they should be easier to clean/fillet/de-bone, though. So maybe I just make it policy to only eat the fish when they are big.

Good work!

JP, the local homebrew place (surprised it's still there, haven't been to it in 8 years at least) has potassium bicarb in 5 oz bottles. How much should I get to start? Dosage per gallon?

I started out putting 2-3 tablespoons per 125gal per day, and now that things are more stable, I seem to need 1 tablespoon per day. My potassium bicarb is a powder--looks a lot like baking soda. You can also get it by the pound through eBay, but then you pay postage, of course.

Well, with my nitrates ranging between 0 and 5 the past couple weeks, I decided it was time to pull one of the RSG filters to see if I could get some nitrates back. I scooped out the sand by hand, and did several sniff tests along the way. At no point did I get a strong anaerobic smell, but mid-way down I thought I got the faintest whiff. When I sniffed again, it was gone--if it ever was there. The upper sand had darkened and was somehow stickier and heavier, but the lower portions were still a nice sand color and the texture was exactly what you expect of wet sand. Perhaps the upper sand just had lots of poo particles in it. I kept the PVC column in place, and just re-filled it with gravel in case I need to put sand back in. Now we will see if I get a rise in nitrates.

I decided that the male breeder was getting a bit crowded with all the 'kids', so I netted out most of the fingerlings, and put the largest 30 into the main grow-out tank. There are still 4 'kids' in with him--they were just a little too fast for me, and I figured I had stressed them all enough for one day. The fingerlings are big enough to eat pellets, so no special provisions have to be made for them at this point. The main tank is still getting 12 tablespoons (60g) of food each day, even though we just ate 5 fish. So I figure that the fingerlings get to eat what those 5 fish would have.

I made a tactical error the other week. The female breeders had knocked their divider loose, and I made a snap decision to remove it rather than wedge it back into place. Their tank glass is algae-covered, and I wasn't cleaning it as well as I should have. Over the next few days, I noticed that there was a lot of crashing and splashing coming from their tank, but wasn't thinking. Fortunately, I stopped to take a careful look at them the other day, and realized that the more aggressive female had run the other one really ragged. Her tail was half the length it should have been, and she had a couple nasty scrapes on her sides. I quickly put the divider in and salted to 6ppt--no plants to worry about. She has made a wonderful recovery now, with the scrapes nearly healed, and her tail showing signs of growing out again. So now we know--focused aggression can be dangerous!

That is a funny statement.

yeah, my son will be using that line I fear.

Had another feast this weekend. The family got together for the October birthday celebration, and I netted out 10 tilapia. Dad helped me clean them, and I learned some technique improvements. They were still too small to fillet, but everyone thought they were delicious. The consensus was to fry them, so I still haven't tried just throwing them on the barbie. Even my 3 year old nephew Jacob tried and liked my 'chicken', even though he really doesn't eat meat. I think I have about 30 large and 30 small fish left in the tank now.

I removed the second RSG filter to get some of my nitrates back. The low-light tropical plants are doing well, and are even blooming. The tomatoes are growing lots of foliage, but only a few tomatoes. I've re-planted the third bed with Asian greens and another try at eggplant. With the days getting shorter, I'm concerned about light levels again. We'll see how that goes.

I'll be putting the breeders back together--probably tonight. One of our newer members could use some fry, so I'll see if the breeders will oblige.

There's nothing like enjoying the fruits of your labour eh Janet?

That's right, you are going into winter there. One of the great things about the tropics. 12 month growing season. aren't Tilapia great?

Janet-

Just wanted to let you know how I made out on getting tilapia for my new system. After several emails with Howard from the FFA about shipping and using breather bags he shipped me 100 UPS his usual way for 50$ total. 50 fish in 2 bags with about half gallon water or less in each bag. Sent on Monday, I received on Thursday about noon. 1 to 2 inch fish, 1 in each bag were dead on arrival, 1 has died since but the rest were and are doing very well and are cute little things. Amazing how well they shipped.

I am very happy to finally have fish in the tank, I was starting to think I would have to pursue your kind offer of fish if I couldn't find some. Thanks for the offer.

Timberdoodle

That's great to hear, Timberdoodle. It's a bit of a drive from your place to mine, so I'm glad you didn't have to do it. Select the best of the best to hold aside as breeders, and you'll be good to go for years.