Backyard Aquaponics
A place to discuss aquaponics

He doesn't look well...
but sorry no answers

A week later and the marron still hasn't changed. It hasn't got worse so I guess that's a good thing.
Found another dead fish today. Been checking the water on a daily basis and all going well. Have been doing water change out ( about a third ) every 2 or 3 days. The only thing different is that we have added a 3rd g/b. Just got landscaping gravel in a bed lined with clear plastic. This has made the water murky but the ph/ amm / nitrate / nitrites are all still good. We did give the gravel a good wash prier to connecting up the bed. Got some photo's if they help. The fish is a bit red on it's nose and it's pectoral fin ( think that's the right name ).

Any "white fuzzies" on the fish in the water? You can't see it when you take the fish out, only when it's in the water....

Can't notice any on other fish. It's a bit hard to see at the moment as the water is still cloudy from adding the third grow bed.Seem to be losing 1 fish every 2 to 3 days. Just have to keep monitoring and changing out water till the system gets happening I guess.

Had another 2 dead fish last night.Yesterdays nitrate level was 8 so we changed about 50 % of the water throughout the day. 1 fish looks normal ( but dead ) the other fish is covered in a thick mucas looking stuff (see photo ). It only died last night.
Can anybody tell me if 5 ( todays nitrate level ) is still too high for small fish. Ammonia is 0 ph is 7.2 temp 11 deg.

My nitrate level ranges between 200 - 300... a reading under 40 is very good, so I don't think the nitrate levels are the problem - looks more like a fungal disease, have you dosed the tank with salt as yet?

Looks to me like you definitely have a fungus due to stress. This is not uncommon especially given the changes you have made and the high nitrite readings. Rx - water changes and add marine salt to the water until the problem clears.

How often should we salt?

Kelly, are you talking nitrite or nitrate levels??

How large is your water volume (for salt amount)

my bad, I didn't read it right. Yeah if the nitrites are at 0 and it is your nitrate that is that high you should have no worries. but you definitely have a stress fungus working there it looks like.

Generally it is good to shock the fungus into disappearing. If it were tilapia I would say 6 per thousand but I am not sure what your species would tolerate without killing the fish. I would say some where between 2.5 to 5 parts per thousand. Caution, some of your plants may be negatively affected. You might want to hand water them for a day or so if they are too delicate.

That's nitrate levels yesterday was 8 today 5. After the water change yesterday we've only got about 750 lt in the tank ( using too much water in the changeouts if we put in more ).Haven't checked the nitrite this morning. Should I ?

Try this then Kelly

The best aquaponic way to treat fish problems is to salt the water - this relieves stress and doesn't harm too many plants if the dosage is ~3ppt (parts per thousand)

1ppt =1kg of salt in 1,000 litres of water (3ppt 3kgs of salt/1,000 litres)

Use uniodised salt (pool salt or marine salt) - not table salt

Mix salt in a bucket and add to the fish tank slowly (like take about 5 minutes to add) - stir water whilst adding if possible

Keep the salt in the tank for at least a month and keep us informed

750 litres = 2.25kg of salt

actually if your readings are within range, you might be adding to the stress levels by changing out the water. I am making the assumption that you are taking care when changing water not to add chlorine?

Basically if readings are good, add the salt and wait The system will usually balance itself in a matter of days.

[quote="dthawk"] I am making the assumption that you are taking care when changing water not to add chlorine?

We are replacing the water with stored rain water so shouldn't be a problem. Have salted the water before but obviously lost it with the water changes. The fish have been getting a bit spooked, need to keep the 1 & 3 yr olds away from the tank. I'll go and salt now.Thanks guys