Backyard Aquaponics
A place to discuss aquaponics

I have had my system going for about three months now and have run into a couple of problems.My Nitrates have all of a sudden dropped from 80ppm to 0ppm within the last four weeks and remain at 0ppm. Nitrites and ammonia are 0ppm with a Ph of 7.6. Temperature of 25 to 30 celius.
I have cut back to feeding my goldfish to once a week but the nitrates still have not changed.
Is it normal for the nitrates to go up and would do you reccomend I should do in order to get them back to 80ppm?
Any advice would be appreciated very much.

There is every chance that your plants are using up the available Nitrate - which isnt a bad thing. Is your plant growth ok? What is your system volumes, FT, GB, fish stock?

A system that is stocked at a good number and is seasoned may well never see any fluctuation in either amm, nitri or nitra. Means the system is working well and the conversion of amm to nitra then plant uptake is all in harmony. You dont need to see a value of nitra for it to be working.

If your plants are growing well and your fish are happy - you are at a perfect stage.

Why did you think that cutting back the feed... would raise nitrates...

[quote="Charlie"]There is every chance that your plants are using up the available Nitrate - which isnt a bad thing. Is your plant growth ok? What is your system volumes, FT, GB, fish stock?

The fish tank holds about 50litres and is about 90cms long by 35cms wide with about five goldfish in. The grow bed slighty bigger than the fish tank. Some of the plants are doing well but some of the tomatoe plants leaves are starting to curl up going a little black at the end of the leaves.

I thought maybe that the nitrates might go down if there is less food for the fish.

Ah OK... well they will eventually...as the plants extract more nitrates than what might be produced by the fish being fed less....

Personally... I'd just add more plants... and feed the fish the same...

I was hoping by feeding the 5 goldfish everyday in my 50litres tank and taking out some plants from the grow bed, the nitrates would go up from 0ppm to 40ppm.
Unfortunely the nitrates didn`t go up and they still remain at 0ppm even though I have had the system going for about 3months now. The plants in my soil garden are going quicker than the one in my aquaponics which is slightly bigger than the fish tank. I only have about 10 small tomatoes plants that are only about 10cms.

Ph 7.6
Ammonia 0ppm
Nitrite 0ppm
Nitrate 0ppm

What do you recommend I should do to get the nitrates up.

Feed more.....

Aquaponics basically boils down to:
Feed in = plants out.

Did you change your feed. Make sure it's more that fish flakes. Get some aquaculture pellets.

I have 10 Goldie's and they produce enough nitrates on trout feed.