Rotten egg smell in skimmer

[skr791346]

Everytime when my PO4 goes past 0.05, my skimmer pulls out skimmate that smells like rotten egg / sulfur. Smell is strong enough to be noticed in the room even when the aquarium stand is closed. When PO4 is low, it just smells like regular skimmate (wet dog / ocean smell).

Not sure if this is relevant but last two ATI ICP tests within one month of each other showed Sulfur at 848.5 & 835.3 against reference values of 863.8 and 773.4 respectively.

I do have a sandbed that ranges from 2 to 3" with some dark spots but I wasn't sure if it was just cyano.

Should I be slowly siphoning out the sandbed?

 

[Richard the Reefer]

If you don't have any pets that clean the sand then you must do it manually. You can research how often. As far as your skimmer I have no idea mate. Happy reefing

 

[Randy Holmes-Farley Verified Community Expert]

The ICP test is not relevant. It cannot distinguish sulfate (good) from sulfide (bad).

I'm not sure why you smell it. Something dead in a hidden spot might do it, especially if partly or completely buried.

I discuss it in detail here:

Hydrogen Sulfide and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-12/rhf/index.php

 

[DeepBlueSomething]

Is the 'sewer gas' smell not considered typical of skimmate? Mine skimmer produces a variety of odors, but there is certainly times it is pulling sewer gas smelling skimmate -- or at least that is the odor associated with the skimmate after a week or so of collection.

Is this a clue / symptom of my tank health that I haven't learned yet? Any articles on skimmate clues? I know it can stink -- and vary in color and consistency due to how the skimmer is tuned...

 

[Randy Holmes-Farley Verified Community Expert]

Is the 'sewer gas' smell not considered typical of skimmate? Mine skimmer produces a variety of odors, but there is certainly times it is pulling sewer gas smelling skimmate -- or at least that is the odor associated with the skimmate after a week or so of collection.

Is this a clue / symptom of my tank health that I haven't learned yet? Any articles on skimmate clues? I know it can stink -- and vary in color and consistency due to how the skimmer is tuned...

Skimmate can have different smells. Many folks say it is horrid, but mine always smelled like the ocean.

It is certainly likely that the skimmate in a cup can become anaerobic if it collects for long, and that is not generally an issue unless the room smells.

 

[Pete1968]

Normal skimmer cup smell! Not to worry! Your skimmer is doing its job

 

[DeepBlueSomething]

Skimmate can have different smells. Many folks say it is horrid, but mine always smelled like the ocean.

It is certainly likely that the skimmate in a cup can become anaerobic if it collects for long, and that is not generally an issue unless the room smells.

Thanks Randy! I so appreciate your chemistry sharing and approach - I enjoy continuing to learn, long long long after chem 101 and O-chem - more fun when not stressed about exams either!

Interestingly, I hypothesize that reefers sensitivity to most tank smells is far less sensitive than our spouses!

 

[skr791346]

The ICP test is not relevant. It cannot distinguish sulfate (good) from sulfide (bad).

I'm not sure why you smell it. Something dead in a hidden spot might do it, especially if partly or completely buried.

I discuss it in detail here:

Hydrogen Sulfide and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-12/rhf/index.php

Thank you Randy. I read through your article a few times and I think I will try siphoning out the sand in portions each week slowly. Based on the pics of sandbed, do you think it's sulfide deposit?

 

[Randy Holmes-Farley Verified Community Expert]

Thank you Randy. I read through your article a few times and I think I will try siphoning out the sand in portions each week slowly. Based on the pics of sandbed, do you think it's sulfide deposit?

I can't judge from the picture. Is it black, or dark reddish? Black is more likely sulfide. You can remove a little and smell it directly, before removing the whole thing.