Question for the chemistry majors here...

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FINWIN

Alligator Gar
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Dec 21, 2018
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This concerns waste/nitrates/nitrites. Everyone knows you don't leave waste in the tank to 'ferment.' But the question is, how long does say solid waste take to become dangerously toxic? Hours or days?

Say for instance you have a messy fish. You clean everything up before calling it a night. The next morning you've got "food tokens" all over the tank. What's your window to get that muck out of there? Immediately? A few hours? If you're a working stiff what if you don't have time in the am to get that. Will the nitrates escalate wildly during the day?

I've often wondered about this. Usually I get stuff as I see it, but fish go when they go...

To my surprise my Severum is pretty messy. The Syno Cat isn't bad. The Parrots...ugh. And the Oscar, 'nuff said. I've literally gone downstairs to find a carpet sometimes. :yuck:
 
Because every tank is different, only you can determine your goal.
When I lived in the states I did a lot of testing on my tanks, and decided 2-5 ppm would be my nitrate goal (because this reflected a way to determine the feces and urine soup concentration in the tank), and if nitrates ever hit 10 ppm, I would immediately do a large water change, whether on schedule or not. This could occur if a fish died, or there was a power outage that compromised filtration and oxygen exchange.
My average water change schedule became 30-40% (with Vacuuming) every other other day on about 1000 gallons of tanks. I was working at the time, so for me this meant getting up an hour early those days to get those water changes in.
Obsessed? Probably.
I was "not " however concerned about particulate and the aesthetics, so much as the chemical quality of the water, because my goal was breeding cichlids, as opposed to display.
I had Pothos and its roots in almost every tank to help suck up nitrate, and these roots seem to attract and release particulate add nauseam.

 
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Will the nitrates escalate wildly during the day?

Not really. It takes a lot of time for solid waste to turn into nitrates. The issue with solid waste is that it takes a lot of oxygen via aerobic decomposition to get broken down to ammonia, which in turn is taken up by the nitrifying bacteria to get converted into nitrates. Nitrate is a chemical non-organic compound that gets dissolved in water but may have an organic molecule attached to it.

In the case of low oxygen conditions, anaerobic decomposition occurs and the bacteria use nitrates instead of oxygen but in that case the process maybe halfway through and nitrites could be released, instead of ammonia, plus the other metabolic waste of that process is hydrogen sulfate and methane, the most common.

In other words, the most important is changing the water, rather than worrying about the waste, and having a well oxygenated tank if the tanks is on the dirtier side. Also, under no circumstances should filters be allowed to collect detritus as the bacteria colony composition will turn into something one does not want. Other than that, removing waste from the tank substrate once a week is just fine.
 
Not really. It takes a lot of time for solid waste to turn into nitrates. The issue with solid waste is that it takes a lot of oxygen via aerobic decomposition to get broken down to ammonia, which in turn is taken up by the nitrifying bacteria to get converted into nitrates. Nitrate is a chemical non-organic compound that gets dissolved in water but may have an organic molecule attached to it.

In the case of low oxygen conditions, anaerobic decomposition occurs and the bacteria use nitrates instead of oxygen but in that case the process maybe halfway through and nitrites could be released, instead of ammonia, plus the other metabolic waste of that process is hydrogen sulfate and methane, the most common.

In other words, the most important is changing the water, rather than worrying about the waste, and having a well oxygenated tank if the tanks is on the dirtier side. Also, under no circumstances should filters be allowed to collect detritus as the bacteria colony composition will turn into something one does not want. Other than that, removing waste from the tank substrate once a week is just fine.

hmm...I have massive aeration in the main tank. It may explain why my nitrates don't really move at all despite 'explosions of solid waste' my fish can put out. My 8 inch O literally covered the base of the 225 in logs one morning...caught me off guard.

I do have a lot of Pothos in the tank submerged which likely helps. I agree with duanes duanes about the particulate matter and pothos roots...as they've grown and gotten longer every time I do a w/c the water goes hazy for a few hours then clears. I'll rinse or wipe the roots down. Usually the haziness happens about an hour after the w/c...the new filter floss will catch a lot of particles after then it clears immediately. Often I will clean the new floss after the first day of w/c. (I keep the filters running until pressure and water level is too low, usually at about 50-60 percent w/c).

The urine issue was really only an ongoing problem in one tank with a BP but I think I've figured a schedule that works for that situation now. The one thing that was never made clear to me is which is the bigger pollutant , solid or liquid form? So apparently the solid waste is more controllable and fixed vs the urine which demands more aggressive control. It explains the situation I used as a comparison in another thread regarding two tanks same size with same size fish, filtration, w/c, etc. The fish with more solid waste had consistent parameters where the fish with higher urine output got spikes.
 
I agree that the solid waste while aesthetically relevant is not as important as the invisible stuff released during metabolism, beside nitrate, it contains hormones and pheromones that also have effect on growth and health, so that the volume of water changed is the most important factor. If power is interrupted, some of those by products can however be seen as an oily or white scum that builds up on the surface of the tank.
Pockets of detritus can be places where bacterial colonies proliferate, so one of the reasons for my insessent vacuuming.
 
which is the bigger pollutant , solid or liquid form?

Liquid waste dissolved in the water column is the bigger enemy. It is an immediate danger to the fish. As you pointed out solid waste is controllable and its effect is delayed. Aerobic decomposition is normal and expected in a tank's substrate and immediately below that zone one has an anaerobic layer which better not be disturbed. In a well oxygenated tank the surface layer of the substrate acts as a massive filter and that's where both nitrification and aerobic decomposition occur. As long as the tank is well oxygenated the top layer remains healthy despite some poop accumulation between water changes.
 
it can however be seen as an oily or white scum that builds up on the surface of the tank.

This is actually a breeding ground for the most pathogenic bacteria such as mycobacterium species. Surface scam should be sucked up during water changes.

Also, some natural mulm accumulation in the substrate is ok as it keeps the micro fauna diverse, which in turn out competes pathogens that become prolific when they have no direct enemies in the form of other micro-organisms. Too dirty is not ok but too clean isn't either.
 
FINWIN FINWIN

Take a look at the probiotics thread in the health section its a long read but worth it. I havent dosed in awhile but products like ridx really do help break down the waste faster.

I cant remember the last time i had to vacuum the substrate in any of my tanks.
 
FINWIN FINWIN

Take a look at the probiotics thread in the health section its a long read but worth it. I havent dosed in awhile but products like ridx really do help break down the waste faster.

I cant remember the last time i had to vacuum the substrate in any of my tanks.

I will definitely take a look at that.
 
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