APD Common Abbreviations

Recently, several postings asked what certain abbreviations meant.  Here's a 
list of common ones.  Address comments, corrections and additions to me 
privately.  I'll update and publish these on occasion.
Rochelle Williams
williaro at ftmcphsn-emh1_army.mil

Aquatic Plant Digest Abbreviations 

C    Carbon
Ca   Calcium
CAE  Chinese Algae Eater (not highly recommended)
Fe   iron
gdh  German degrees hardness
GH   general hardness
H    Hydrogen
hygro     hygrophelia (fast growing aquatic plant having many varieties)
K    Potassium (type of fertilizer)
KH   carbonate hardness
Mg   Magnesium
N    Nitrogen (type of fertilizer)
NO2  nitrite
NO3  nitrate
O    Oxygen
otto (also oto) - Otocinclus (a recommended algae eating fish)
P    Phosphorus
pleco     (also pl*co) - plecostomus (various species of algea eating fish)
PMDD  Poor Man's Dupla Drops (homemade liquid fertilizer)
PO4  phosphate
ppm  parts per million
S    Sulphur
SAE  Siamese Algae Eater (eats red algae)
val  vallisnaria
<    less than (see greater than)
>    greater than (as in >3.0ppm greater than 3.0 ppm)