Abbreviations

Anyone please feel free to add to this list if I missed anything,

AC- Activated carbon, chemical filtration media / alternating current
AFM -Aquarium Fish Monthly, magazine
AGA- All-Glass Aquarium, Aquarium manufacturer
AL- Aqualink, aquarium bulletin board
ATS- Algae turf scrubber, reef setup technique
BOD- Biological oxygen demand
CC- Counter current, type of protein skimmer
CSL- Custom Sea Life, lighting manufacturer
CTA- Cellulose triacetate, type of RO membrane
Cyano- Cyanobacteria
DC- Direct current
DD- Downdraft, type of protein skimmer
DI- Deionisation, type of water purification
DIY- Do it yourself
DSB- Deep Sand Bed
FAMA- Freshwater and Marine Aquaria, magazine
FFE- Flying Fish Express, Mail Order Company
FO- Fish only
FOWLR- Fish only with live rock
FW Freshwater
GBR- Great Barrier Reef
GPH- Gallons per hour
HO- High output fluorescent light
HQI- Mercury (Hg) Quartz Iodide, a type of metal halide lamp
IA- Inland Aquatics, mail order company
IMHO -In My Humble Opinion
IMO- In My Opinion
IO- Instant Ocean, brand of aquarium salt
IR- Infrared
Kalk- Kalkwasser, German for calcium hydroxide solution or limewater
LFS- Local fish store
LHS -Local hardware store
LPS- Large polyped Scleractinian (stoney) coral
LR -Live rock
LS- Live sand
MACNA -Marine Aquaria Conference of North America, held annually
MASNA- Marine Aquarium Societies of North America
MD- Marine Depot, mail order company
MH -Metal halide light
MJ -Maxijet, powerhead manufacturer
MM- Miracle Mud, method of aquarium filtration
MO- Mail order
NO- Normal output fluorescent light
NSW- Natural seawater
PA -Premium Aquatics, mail order company
PC- Power compact fluorescent light
PH -Powerhead, water pump
PVC -Poly vinyl chloride, used for piping / plumbing
RC -Reef Central, aquarium bulletin board supreme
RC -Reef Crystals, brand of aquarium salt
RDO -Reefs.org ("reefs-dot-org"), aquarium bulletin board
RK- Reef Keeping, on-line aquarium magazine
RO- Reverse osmosis, type of water purification
RO/DI- Reverse osmosis, followed by deionisation, type of water purification
RR- Reef ready, aquaria with pre-drilled holes and overflows
RTN -Rapid tissue necrosis, protozoal infection of corals; can be rapidly fatal if not treated
SG- Specific gravity
SPS- Small polyped Scleractinian (stoney) coral
SW- Saltwater / seawater
TBS -Tampa Bay Saltwater, Mail Order Company
TFC -Thin film composite, type of RO membrane
TRT -The Reef Tank, aquarium bulletin board
TWP -Tap Water Purifier from Aquatic Pharmaceuticals
UGF- Undergravel filter
UV -Ultra violet light
VHO -Very high output fluorescent light
W/D- Wet-dry (a method of aquarium filtration)
WD -Wet-dry (a method of aquarium filtration)