Backyard Aquaponics
A place to discuss aquaponics

have around 20 rainbow trout in 1000lts of water, they look healthy but have gone of their feed the last fews days, is this normal or do I need to change things, I run a 4500lph pump 15mins to the hour during the day and 2 15min setions at night, all though I dont have standarded growbeds I have about 3 grow beds of plants. Any help would be great
Cheers
Don

Hi Don, and welcome to the forum...

Do you have a test kit to test your water parameters?

Can you provide us with pH, ammonia, nitrite, nitrate and water temperature values?

The trout may have gone off their feed if some of these values have changed in recent days or reached levels over a period of time....

A sudden rise or fall in water temperature may also be a cause for their behaviour.

Regardless... basic rule of thumb is .... if the fish aren't feeding..... don't feed them....

Un-eaten food will just settle to the bottom, decompose and possibly exaserbate any water quality problems... including robbing DO from the system....

Trout are severely dependant on DO, although they have appeared to be happy in the past with your current pumping cycles it may be that other varibles are removing DO from the system....

A quick way to address this would be to increase your pumping cycles/times ... or run your pumps continuously for a while....

Test results would help us diagnose the cause and courses of action...

hi don,

my rainbows also stopped feeding for two days, i found it strange and was going to test water on the third day, but they came good!

Yep, not uncommon for fish to go off the feed if there's a sudden drop in barometric pressure... like a strong cold front sweeping through....

When the batch of trout I had a few years ago,
didn't want their tucka,
I'd would shell peas, the frozen one are ok but I am sure a few spare
freshies would be good!
If ya squish the pea sort of gently on the side 2 half spheres will pop out!
Trout love em!

When Gnash had trouble getting his to eat, we found that flicking the food into the water with great force, to cause a splash - made them eat well

So OBO , your saying you got so angry at the trout you threw pellets at them ,, THEN discovered that they would eat that way ?
I bet this "discovery" happened in conjunction with a few amber ales.

Nope, just by accident. Dropped a couple from up high and they looked interested.

DAm ,, was sounding like a good story until FACTS got in the road.

Ours go off the feed when the PH drops too fast.

Hi Rupert I don't have a test kit but the water is 13degres c and the ph is 6.4 .I left the pump running for twenty four hours and they seem quite happy again now .I had computer prblems that stopped me contacting everyone sooner. Thanks to everyone, Cheers ,Don.

Trout like do and moving water if you want to run trout you will need at leased one large airstone in there tank the air rising will move the water my 50 get up to 4 handfulls of food a day [i turn my pump off from 5 pm to 8 am]

Nothing to suggest a problem with pH 6.4 and temp 13 degrees Don.....

Think it's most likely DO.... many fish (and peoples AP systems) probably run 5-6 DO... with a high of maybe 8......

Trout on the other hand probably begin to struggle at the range 5-6.... preferring 10-12.... their preference for cold water makes these levels acheivable... DO is increased in cold water...

They also like high flow rates.... so if you can keep your pumping rate continuous or at least high flow for regular periods... and add some supplementary air as F&F suggested....

Your trout should grow into giants :d

Here's a background article for you .... specific to WA trout .... http://www.fish.wa.gov.au/docs/frr/frr130/frr130.pdf

My trout wont eat in the mornings when the pump has been off overnight. I would assume DO is too low for them first thing.

Mine are feeding good now, i'm up to a hand full of feed twice a day and no remaining pellets on the tank floor.
I'm slowly increasing the feed amount but they are gutses and will eat until they pop