Almost every hobbyist has experienced the dreaded White Slime or as some call it "Killer Mucus". There is a rhyme and reason to why it occurs as well as a process to remove it!
Many will call out the obvious that it is a bacteria bloom but they have a hard time identifying the "why" or root cause so most are left scratching their heads OR worse get discouraged and quit the hobby!
We are here to tell you that we have encountered it dozens of times on both new and well established tanks and it has NOTHING to do with balance or parameters (within reason anyways).
Where and Why?
This white slime/mucus is caused by VOC's (Volatile organic compounds) that build up in your tank, they are a form of food for carbon hungry bacteria. These compounds can come from a variety of things but the usual culprits are household items no one thinks about...
We have tested these theories and each time proved they were the cause of this nasty slime! Some of the things we have seen that have positively caused VOC's to build up and feed your tanks bacteria are as follows:
- Gasoline/fuels
- Solvents (so if doing some plumbing in your home or on your tank)
- Silicone
- Paints, stains, etc
- Pesticides
- Aerosol Sprays (the hair spray, oh man is this bad!)
- Cleaners and deodorizers (seen scents burning or wicked off in rooms from scent machines etc cause this issue)
- Even new things like rugs/floors,carpets etc, crazy but TRUE.
Many people have reef tanks in either their main living areas OR a Man Cave/Garage/Basement. Even if tanks are in the main living area we have seen and heard of many sumps being in a utility closet or storage area to hide and save space and avoid the noise. This is all great BUT many of these areas tend to have some of the highest concentrations of VOC's and are problematic. Even if you get control of your issue the stuff just comes back...
So, as for Avoiding this issue the only ways are to avoid VOC producing things in your home the best you can and try and have Carbon/HEPA filters in your HVAC or in the room with your tank/sump etc.
How do I get rid of this stuff?
Unfortunately, there is no "Easy" way to remove or just get rid of this stuff. Usually it requires manual intervention like blowing off the rocks or sand/plants with something and using a net to catch as much of it as your can.
Once you have collected as much as you can the next steps are somewhat easier.
Turn off your carbon reactor and clean out and replace (leave off)
Turn off your UV
Turn off your skimmer and clean out (leave off)
Change your filter socks or filter medium (wait 30 -60 min after cleaning tank to ensure as much of the stuff is caught in filter media as possible). If you see filter media getting full and about to be overwhelmed then change it right away, and try not to let water get past your new media if possible!)
Every day keep repeating the same process, blow off things and collect everything you can manually and change that filter medium.
Do NOT dose chemicals or bacteria or other products promising magic results!
Within days of doing this process you WILL see positive results. It could take a week, it could take a month but it will get better but will take work daily. It is best to catch this issue early and start the process of cleanup right away rather than hoping it will just "get better" on its own.
What to watch for
As we said, most people catch it late and have to work harder and longer to clean up their reef BUT it can be noticed early and resolved within days from that point.
Some simple signs to watch for are:
- slime on top edges of tank or water line in sump
- filter media/socks getting dirtier faster than usual but look clean (this is usually sign the slime is getting caught which is good but it causes media to be overwhelmed and then fail and allow water to spill by)
- snot looking strings here and there within display or sump tanks
If you notice any of these things don't panic, don't dose, don't water change, and most importantly DO NOT quit the hobby! Perform the 4 main steps we called out and change your filter media/socks every day (This is KEY).
We hope you found this information educational but more importantly we hope it helps next time this occurs, and it WILL!
- Florida Reef Labs