Backyard Aquaponics
A place to discuss aquaponics

I received 10 trout from Rupe on saturday, 5 of the little buggers went over the wall the first night!

Have (as of sunday morning) covered tightly with shadecloth, only problem is now that I have to lift the lid to see how things are going

Steely

Told ya ....

Wondering if anyone could give some info on the best way to weigh fish?

The method I've used is to wet an aquarium net, tare it on the scales, collect a few, weigh and average the mass. The problem with this, is there could be more water attached to the fish and the net, over exagerating the fish mass. I'm also concerned about handling the fish, obviously want to keep it to a minimum.

Any ideas?

Might be better to use a bucket Geoff... and maybe weight 5-10 fish... then average..

Yep, did that Rupe. The bucket method showed the same result.

The thing that threw me off, was the initial average weight when I recieved the fish was 32 grams and after two and half weeks I'm getting 58 grams (average weight of 15 fish). If this is a real and relatively accurate measurement then I'm absolutely rapt. Is this what you would expect from trout?

FYI...bream are doing well. Added two more today and also two Blackfish from the river at 302 and 410 grams each. Will be interested to see how they go. Do you know of anyone trying blackfish?

Good to know Geoff... and not surprising...

Hadn't had the time to weigh any out of the tank... but after a couple of weeks feeding the last lot I delivered were obviously growing....

I'd better advise Bree to up her feed rate....

So how many grams have you been feeding each day Geoff??

Want to reconsider your feed purchase....

Started at 122.5 grams per day (70 fish@35grams), based on 5% of fish weight (a bit too high...I know). Dropped that back to 90 grams (3.7% of fish mass). The initial high ammonia levels of 4.0 ppm are now at 0.25 ppm, nitrite at 1.0 and Nitrate a steady 10 ppm. ***Please note to all - this is not an aquaponics system. It is an "aquaculture setup" based on bio-filtration and 5% daily water change in a 1000 litre tank***

Revised calcs, at tonights increase in weight, suggest 124.0 grams per day at 3.0 % feed of total fish mass.

While water parameters look good I will continue at this rate until parameters or fish health suggest otherwise.

I am recording feed rates, increased fish mass and water parameters on a daily basis and hope to create a feed per fish mass relationship I can use next time round (for this size system).

Ideally I'd like an equation I can use to calculate feed rate at any given point during growout.

As far as more feed goes Rupe...the missus is already jumping up and down about the money I've spent on this!!!

I'll have to take a month at a time! She'll come around!

Troutman suggests a feed rate of 1% of biomass Geoff...

Refer to this post by Troutman for some weight vs feed rate Geoff...
viewtopic.php?p=188602#p188602

Just wondering.....for those who received trout from Rupert, how are growth rates looking? Anyone had any dramas?

Water colour in my 1000 litre BYAP tank is getting pretty murky. The AP, IBC tank with 20 trout is nice and clear. All fish doing well though, with no recent losses.

Size is between 120 and 150mm. Haven't weighed for a couple of weeks now.

Hi there
My trout are growing a bit but I have only been feeding them limited food because the system hadn't cycled. It has now and I have upped it to 4 table spoons a day and the water is crystal clear and all readings are 0 but my PH has dropped to 6.2 so i have added a little ph up to bring it up. All in all fish are happy veg is happy, tummy happy.

The part about havent weighed for a week has me worried dipping around in the tank is only stressing the fish it will only be a mater of time and you will have stressed fish and they will start dying

Your right F&F. From now on I'll just eyeball the length while they are swimming around. It's a bit hard getting an accurate average weight anyways.....