Backyard Aquaponics
A place to discuss aquaponics

And it did

Ammonia is back down to 0 but my nitrite readings are still off the charts, even after diluting the water to 50%...

Waiting for them to zero out so I can get my perch.

Down to 1 goldfish from my initial 9. Ah well It was going to happen.

Once cycled, I'll buy some more to live in the sump for my kids to look at/feed etc.

Just because some added ammonia has been converted and the resultant nitrites converted too, in my book, this doesn't mean too much. In order to deal with a continuous load of ammonia and waste from fish, you need to have sufficient colonies of bacteria established, not just small "outposts" which can deal with an occasional dosing of ammonia. If within 24 hours of dosing your system, the ammonia and nitrites return to their zero levels, then you are what I call "fully cycled" and can demonstrate sufficient bacterial colonies to deal with waste in a timely manner, even continuously; IMHO it's safer to add fish at this stage than any earlier. It's going to be a little harder, but not impossible to tell what the zero level is as you're dosing the system which also contains a few surviving goldfish (but seeing as you only have 1 survivor...)



The bacteria to convert nitrites to nitrates don't flourish in the presence of high concentrations of ammonia, so it's only now that your ammonia has fallen that you'll start to see an increase in the conversion of nitrites to nitrates; you've still got a way to go, so be patient, remembering that the most important part of the AP system is not the fish or the plants, but the bacteria. And, like fish and plants, bacteria don't like sudden changes either i.e. sudden temperature changes, pH changes, salinity changes etc can cause bacterial shock or bacterial crashes which stymies the nitrification process, so wastes build up and eventually the fish die too, followed by the plants.

If you're only going to have a very light stock density, fish can be added at almost any time. If you're aiming at the higher end of the density scale i.e. 1 fish per 20L of filtration, then I reckon it's safer for the fish to wait until fully cycled before adding a load of fish, and even then, feed them lightly for the first few weeks to minimise the additional waste generated so the working bacteria can adjust to their new loading.

In any event, a little patience now will pay dividends later. Your SP will take a year or more to grow out to eating size, so waiting a little bit longer now to ensure the system is 100% ready to receive them is not going to matter when harvest time eventually comes around. If you're not the patient type, then think of it like this; every fish you don't kill at the beginning is going to save you money

Yes I agree with you and that is why I have not added any more fish at this stage. I had ammonia and nitrites extremely high, ammonia is back down to 0 and I'm hoping the nitrites will retreat from their heights soon. I didn't bother to test yesterday as the day before they were still maxing out the colour chart.

Once all my readings, other than nitrates are back at 0, I will add more fish. Not before. At this time, given my 1400l of filtration and 1000l tank that should be sufficiently cycled to support a population of 25 SP fingerlings.

On a positive note, my lettuce is going gangbusters, strawberries are growing fruit already and tomatoes have flowers on them... I've snipped off a few lettuce leaves to eat thus far.

As usual, thankyou for your indepth and valuable feedback Bunson.

my nitrites have finally dropped to 0 now. 0 ammonia, 0 nitrites, pH around 7.8 or so... haven't bothered to test nitrates because I don't care... safe to add SP now or should I spike my ammonia first and see how it reacts?

Bunson would say yes. I usually don't bother. But then again, I usually don't loose all my fish during cycling. And I usually let them stay in the system on a normal feed rate for a few weeks after cycling, just to ensure that everything is okay.

Since you are down to 1 goldy from 9, you probably need to do some type of test. I think you have two options:
1) if you are desperate to get 25 silver perch in ASAP, I would intentionally spike the ammonia first to check you are all good.
2) otherwise, if you have patience, I would add 5 feeder fish twice a week until you have 10-15, if none of them die, then the system should handle swapping them out for the silver perch....this the way I usually cycle, but can be expensive if you have no other plans for the gold fish.

Just add fish.. test... and adjust you feed rate accordingly...

Rupe has the faith in him

Rupe does not believe in fishless cycling. In the words of Captain Ron " Well, the best way to find out is to getter out on the ocean, if anything is gonna happen, it's gonna happen out there."

Neither do I. But I would not consider this cycle to have been a smooth one considering 80% fish fatality, so would not trust the system to take 25 new fish in one go. I advocate getting fish in there, whether you take a structure approach like I said, or just whack them in and ride the ammonia waves ....keeping with the ocean analogy.

I have cycle aquariums for years using my "add a few fish at a time" method without the need for any test kits.

The goldies were always going to be lucky to live... I ignored everything I read on here and kept dropping a bit of usea in there every few days because I wasn't getting any amonia readings even after a week or so... then I added the goldies. Eventually it spiked but unfortunately for the fish, i had nowhere to put them.

It is what it is. I don't particularly feel bad. Fish die, such is life.

The system is properly cycled now. I poured in some leftover 25% ammonia yesterday but didn't have time to wait for the water to mix properly and test so I don't know what my initial reading was, but this morning there was not a trace of ammonia or nitrites. Ordering SP. Rupe, email inc.

Good stuff.

Not worried about the gold fish either

I'll try and move the goldfish to the sump... if I can catch it.

No email received...yet...