Strange things a'happening in my tank.....

HI (again!)

110 Litre (approx 26 gallons)
Set up for about a year

Home to: 6 Panda Corydoras (2 large & 4 babies), 9 Neon Tetras, 1 Bristlenose Plec, 3 Assassin Snails

1 Baby cory is MIA so can currently only see 2 large/adult and 3 babies

Water Parameters using API Master Test Kit (readings done within last 10 minutes)
Ammonia: 0
Nitrite: 0
Nitrate: Struggling to read but seems high. It's dark here now so can't use natural light and i've bad light in my house. Different places seem to give different readings..

40% weekly water change with gravel hoover - done twice a week if needed

I say strange things are happening as 1 baby Cory is missing (none appeared unwell and they can't jump the tank) , the neons are quite tightly schooled together tonight (normally relaxed and spread out) and the 2 adult corys are chasing each other more than normal. In fact one seems to have his snout pushed against the others abdomen alot. The BNP seems more than happy and oblivious to anything else

The 2 adult corys have always been together (was just the 2 of them for ages) and even with the younger ones in the tank, these 2 are always together.

What could have caused my nitrates to shoot up? Why are the neons tightly schooling tonight (compared to normal) and could the corys be breeding??

Argh so much time and energy (and money!) has gone into my tanks I'm in a constant state of worry

 

If one of the corys is missing than it's possible that it's decomposing somewhere which could cause your nitrates to rise resulting in your other fish acting a bit off.

I would try to locate the missing cory.

And I don't know much about their breeding behavior so I can't help you there.

 

How big is the pleco? They can grow to 6 inches and have a big bio-load. Could explain the increase in nitrates and why your fish are acting strange. Something to think about.

 

How big is the pleco? They can grow to 6 inches and have a big bio-load. Could explain the increase in nitrates and why your fish are acting strange. Something to think about.

Its bn pleco, so it doesn't get that big, usually I have "lost" one or two cories for a few days then I just find them there one day munching and losing them again. How long have you lost the baby cory.

 

You still have to take in to consideration the fact that they can grow to 6 inches.

 

BN is only about 2 inches at mo. I know they can grow to about 6 and more frequent water changes and maintenence aren't a problem, I have the time. I have no plans for antthing further to go in the tank.

Wouldnt a decomposing body cause ammonia spike? And the baby was only just over 1 cm long so quite a small thing in a large tank.

The 2 adults have always stuck together and chased and played, they just seem to have stepped it up a gear.

I'm planning to do a large water change this morning and have another search for the baby. Its not the first time ive assumed one missing and have found it snoozing somewhere but when I feed them they usually do all pile in. Hasnt happened this time.

 

If one of the corys is missing than it's possible that it's decomposing somewhere which could cause your nitrates to rise resulting in your other fish acting a bit off.

I would try to locate the missing cory.

Missing cory located ALIVE! Removed 50% of the water, upturned everything and it was just sat there watching lol, Ah well, extra water change for them .

Still no idea what caused the nitrate spike though. Everyone is acting normal again today. I left the test I did as I really couldn't read it last night and this morning it was showing 40ppm but the test was 8hours old by that point.

Will just keep an eye on things.

 

Glad you found him safe & well