I'm settting up a new tank and strongly considering an aquamaxx denitrator.
The only thing holding me back is the bad reputation (the why don't more people use them that's been discussed in this thread) and H2S concerns.
Regarding H2S, how have you dealt with this when the reactor gets out of balance? How bad is the smell and how long does it take to go away? Have there been any studies on what levels of H2S can be produced from a denitrator? In my case, i'll be going with the large TS3 model for a 500gal tank.
Below is some safety information I found on H2S:
Exposure to lower concentrations can result in
eye irritation, a sore throat and
cough, nausea, shortness of breath, and fluid in the
lungs(
pulmonary edema).
[25] These effects are believed to be due to the fact that hydrogen sulfide combines with
alkali present in moist surface tissues to form
sodium sulfide, a
caustic.
[30] These symptoms usually go away in a few weeks.
Long-term, low-level exposure may result in
fatigue, loss of appetite,
headaches, irritability, poor memory, and
dizziness. Chronic exposure to low level H
2S (around 2
ppm) has been implicated in increased miscarriage and reproductive health issues among Russian and Finnish wood pulp workers,
[31] but the reports have not (as of circa 1995) been replicated.
Short-term, high-level exposure can induce immediate collapse, with loss of breathing and a high probability of death. If death does not occur, high exposure to hydrogen sulfide can lead to
cortical pseudolaminar necrosis, degeneration of the
basal ganglia and
cerebral edema.
[25] Although respiratory paralysis may be immediate, it can also be delayed up to 72 hours.
[32]
- 0.00047 ppm or 0.47 ppb is the odor threshold, the point at which 50% of a human panel can detect the presence of an odor without being able to identify it.[33]
- 10 ppm is the OSHA permissible exposure limit (PEL) (8 hour time-weighted average).[16]
- 10–20 ppm is the borderline concentration for eye irritation.
- 20 ppm is the acceptable ceiling concentration established by OSHA.[16]
- 50 ppm is the acceptable maximum peak above the ceiling concentration for an 8-hour shift, with a maximum duration of 10 minutes.[16]
- 50–100 ppm leads to eye damage.
- At 100–150 ppm the olfactory nerve is paralyzed after a few inhalations, and the sense of smell disappears, often together with awareness of danger.[34][35]
- 320–530 ppm leads to pulmonary edemawith the possibility of death.[25]
- 530–1000 ppm causes strong stimulation of the central nervous system and rapid breathing, leading to loss of breathing.
- 800 ppm is the lethal concentration for 50% of humans for 5 minutes' exposure (LC50).
- Concentrations over 1000 ppm cause immediate collapse with loss of breathing, even after inhalation of a single breath.
