Hydrogen Sufide and Calcium Reactor

[reefswimatl]

I've had a calcium reactor for years and just encountered something new.
Hoping someone out there can comment...

Is it normal for the gas bubbles that occur near the top to contain hydrogen sulfide gas?
I noticed the smell the other day when I was "burping" out the gas. I don't ever remember smelling it as strong in the past, and in fact I always assumed those extra gas pockets at the top were accumulated CO2.

So I'm a little concerned something may be wrong.
The flow rate into and out of the reactor seems to be fine, and the recirculating pump seems fine too (I have a Koralin reactor).

If anything the CO2 injection may have been running a little slow (although the media level is going down indicating it is slowly dissolving).
I have to admit I am not testing the PH of the effluent, and I don't have a controller.

Can the anaerobic bacteria that generate H2S even live in a low PH environment found in the reactor?

Any ideas?

Thanks!
Tom

 

[cdub]

I believe if the reactor sits dormant it can generate hydrogen sulfide

 

[acroholic]

If you are getting H2S smell (rotten eggs), I would immediately stop the calcium reactor, take it apart, wash the media and the reactor, and inspect the media.

I would gues one of two causes:

1. Too slow an effluent rate thru the reactor, as that is the primary reason this happens in nitrate reactors.

2. Another possiblility is that your media has dissolved/softened to a point that it is compacting and forming dead spots where the H2S gas is forming. Look for black areas if you do remove the media. Might be time to replace it and run the reactor at a slightly higher setpoint. Large media can be run lower than fine media.