Backyard Aquaponics
A place to discuss aquaponics

Thaks for the feedback Ivan and Nocky
You are right, it is difficult to tell the difference from 1 to 5
I have not fed at all today and I added some shellgrit yesterday.
The readings this afternoon showed the PH had risen from 6.6 to 6.8 the Rites still at around 5 (maybe) and Rates the same at 10. My ammo had also dropped from 1 to 0.5.
I am reasonably comfortable with what is happening so I will hold off on the feed for another day and test tomorrow afternoon. I will resume feeding when the Ammo and Rites are both back at 0 or close to.

Here are the readings for tonight

PH - 6.8
Ammo - 0.5
Rites - 5
Rates - 10

That is 2 days now without feed so I hope tomorrow shows the Rites starting to fall. The little fella's thinks their throats have been cut. Daily feeds - now nothing.
I have also salted again tonight for another 1 ppt as with all the rain we have had over the past few days I figure it may have been diluted and if not it certainly cant hurt.

Just a quick question around the salting of the FT.
Can you just add the salt direct to the FT or do you disolve it in a bucket first ?
I have been disolving it but I thought I would ask the question.

I would personally dissolve it first if it is going in with the fish. (Avoiding the case of concentrated amounts going through their gills)

Thanks Faye I thought it was the best option.
I had visions of the little fella's eating the salt they are that hungry

I need some advice on the Nitrite issue
My water tests are not showing any drop as such in the Nitrite reading
I have not fed since Monday and the Ammo reading has dropped to 0.25 but the Nitrite has remained somewhere between 1 -5.
I have salted twice to 1 ppt as a mitigation against the Nitrite the second time only because of the amount of rain we have had has meant me dropping the water level a couple of times.

I have decided to give them a small daily feed and continue with this as long as the Ammo does not rise to much again.
I am asuming the second stage of bacteria is still a bit slow due to the weather.

Readings this morning
PH - 6.6
Ammo - 0.25
Nitrite - Above 1
Nitrate - 5

Anyone

Hmm... no one is around...

The stage you are in takes a few days or even 1-2 weeks depending on the weather to get pass. And yes, it is because the second stage bacteria (nitrobacter or nitrospira; depending on who you believe) takes twice as long to grow plus cold weather slows it down even more.

Some would tell you not to feed at all, because without feeding, ammonia is still produced. But if you are leaning towards the side where you are concerned about starving the fishes, just feed them a little. You do not want your ammonia to rise at all.

There is not much you can do at this stage of the cycling, just salt to at least 1ppt (I salted to 3ppt) and leave the system running. Do not do any water changes or anything unless you noticed a change in the water quality or change in fishes behaviour.

Have you added shellgrit yet? Watch your pH of 6.6, and as your system gets cycled, pH will drop even more.. Also remember to check the shellgrit, as if they have dissolved, you need to add more.

Thanks for the response Ivan

As I said in my earlier post I could not starve the little fellas for another day. Yes I did put in the shell grit but I havent seen any sign of the PH moving as yet.
When you say keep the system running are you saying run it continuous or just on the normal timer cycle ?

Well I meant system running as in running as per your normal cycle.

I have not actually been able to actually correlate this yet, but I think continuously running or at least increasing the timer on duration during system cycling does help to speed up the ammonia to nitrate conversion process.

Your Nitrites have dropped off markedly from the other week... indicating you are virtually "cycled" ....

Feed lightly tomorrow... and retest... if your values stay the same repeat feeding the next day... if you then get a slight rise in ammo... skip a day....

Repeat until you can feed daily... then adjust feed to what you should be feeding using the same method...

Shellgrit is a "slow release" buffer... and might take some time to change the pH...

How much did you add??

In the mean time, increasing your feed as the bacteria colony increases will most likely pull pH further... keep an eye on it...

If need be use a faster acting buffer as posted in numerous threads...

Thanks for the feed back Rupe

I do have a lot of trouble distinguishing the difference between 1 to 5 on the Nitrite colour chart but I still think it is more likely closer to 5 than 1 hence the "Above 1"

I have added 2Kg of shell grit next to the return pipe from the GB's to the ST. I will do a search on the other buffering solutions and bring it back up.

Just for my own piece of mind what would the longest time be that you would be able to not feed the fish and them not be harmed in any way ?

Depends on fish species to some extent... stage of growth... but probably more to do with water temp...

Most fish (other than very small fry/fingerlings) will survive a week or more....

I will stick to the small daily feeds and the daily water tests as suggested.

I do not see any evidence of stress or poor health in the fish. They are all very active and are content to school together in the current created by the pump bypass line when running. I have two air stones in the tank and a venturie on the return line from the Sump to the FT. This boils the water with air when it runs.

Thanks again to both of you for the info