Backyard Aquaponics
A place to discuss aquaponics

I also got nitrite around 5ppm without an ammonia reading above 2ppm.

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Yea, I think it is because a strong colony of nitrosomonas developed early, but it is taking a while for the nitrobacter to catch up.

Quite possible... but a nitrite reading of 10+... doesn't make sense.. unless the ammonia reading was way higher than 2ppm at some stage...

It was just 10, not 10+

That still represents a high ammonia reading at some stage...

If there was, then the nitrosomonas brought it down before it was tested. I test once per day, in the evening. So if a major spike happened at night, it would have had the whole day to smooth out. Early on, quite a few fry made their way into the plumbing, I saved some, but about 20 or so died. That was when I had the 2.0 ppm reading in ammonia. It could have happened then, but I never *measured* over 2.0 ppm in ammonia. I also haven't had any fish deaths not related to the plumbing incident. (A couple of ones that were in the plumbing were pretty injured but I put them back, only to have to scoop them out the next day)

Well the ammonia must have been there... the process is as follows...

There's a couple of intermediate steps... but it can be summarised as...

NH3 + 1.5 O2 => NO2- + H+ + H2O

So you can see that it requires the same amount of nitrogen (NH3) in... as nitrogen (NO2) out....

Or to put it another way... by the formula...

10xNH3 + 15 O2 => 10xNO2- + 10xH+ + 10xH2O

Sure, all I was saying is that the ammonia got converted before it was able to be read. People have high nitrate readings, with their ammonia and nitrite reading zero all of the time. That is a happily cycled system. High nitrites and little ammonia is just a half cycled system. My system has had fish for about 2 weeks now, so I have a half cycled system. I don't want anything bad to happen to my tilapia, but I was prepared for losses. After all, they were likely to be a part of a massive die off in their original home. If I lose them, I will get more, but my system would be cycled already, so they would likely thrive.

Today's numbers:
Ph 8.2
Ammo .25
Nitrite 10
Nitrate 40

We had our first harvest today! My in-laws brought over some pizza, and I thought some fresh basil might be a nice addition. It tasted fantastic!

I did a partial water change today. I know everyone says that it slows the cycling process, but I wanted to get the nitrites under 5. It worked. The full strength sample is still the undescernable purple. I did a 1/10 th dilution, and it is .25. Actually it is a tiny bit bluer than .25. So that puts me at about 2.5 ppm for nitrites.
Ph 8.2
Ammo .5 ppm
Nitrites 2.5
Nitrate 40
I also modified my SLO. I moved it towards the center of the tank more, and used a larger mesh net from a laundry bag. The other net just cloged too much, I figured any fry that are left that are small enough to fit through, might be runts.

glad to see things are coming along....

My favorite word is "Modify" so I do it all the time

Modification is all part of the process....

jT

Today's numbers,
Ph 8.2
Ammonia .25
Nitrite 2.5
Nitrate 40

Ph 8.2
Ammo .5
Nitrite 1.25
Nitrate over 40, under 80
Should the ph have dropped some by now? Is it too high? Should I add something to lower it to prevent nutrient lockout? Some of my plants are looking kind of yellow.

I added the juice of a lemon today to gently lower the ph some. I added it after I measured the ph.
Today's numbers
Ph 8.2
Ammo .25
Nitrites 1 ppm
Nitrates 40 ppm
For some reason at full strength, the nitrites are too purple to discern, but at half dilution it shows as .5 ppm. Wierd.