I have two fish tanks: a 65 gallon freshwater Amazon set up and a 72-Gal. saltwater reef tank. I kept freshwater fish from my childhood and it was relatively easy to switch to the marine aquarium keeping. I kept fish-only tanks and some invertebrate / fish combination set-ups, but settled in for the reef tank for its beauty and natural self-maintenance. Although marine aquaria attract much greater attention and definitely look brighter in your home, I still like keeping my freshwater planted tank: it is virtually maintenance-free once everything is under control and it, I guess, after having freshwater fish for my entire life it just feels wrong not to have a tank.
My current marine aquarium set-up includes the following:

Fish:
- 2 ocellaris clowns (Amphiprion ocellaris)
- 1 blue hepo tang (Paracanthurus hepatus)
- 1 yellow tang (Zebrasoma flavescens)
- 1 bi-color pseudochromis (Pseudochromis paccagnella)
In the past I also kept dwarf lionfish with some success. Lost two of them while on vacation because of their eating habits, or, should I say, training.
Inverts:
- Scarlet skunk cleaner shrimp (Lysmata amboinensis)-parasite control
- Black Atlantic sea cucumber (Holothuria floridana)-detritus control
- 5 sea hares (Aplysia slugs)-hair algae control
- Margarita (Margarites pupillus), Conehead (Astraea tecta), Nassarius, Nerite, and Cerith Snails
- Dwarf hermit crabs
Corals:
- Trumpet (Caulastrea curvata)
- Bubble (Plerogyra sinuosa)
- Hummer/ anchor (Euphyllia paranchora)
- Toadstool leather (Sarcophyton sp.)
- Kenya tree (Capnella sp.)
- Mushrooms (Actinodiscus, Ricordea, and Rhodactis indosinensis)
- Colony polyps (Zoanthus/ zoanthid)
- Button polyps (Protopalythoa)
- Starburst (Briareum)
- Xenia
- Anthelia
My freshwater tank currently is stocked with:

angelfish, discus, emperor tetras, and rainbow fish (boesemani and red irian). For years I relied on plecos for algae control, but this limited my choice of live plants. I recently discovered the power of Otocinclus catfish for clearing algae without destroying sensitive plants.
Other the years I experienced a variety of problems while experimenting with different fish, inverts, and corals. I have learned the methods of slime, diatom, and hair algae control from trial and error, spending hours and bucks on research and different products. I will be glad to share my experience/compare notes with others in the hobby. As a big fan of the natural solutions to the aquarium problems I tried to stock my tank with compatible and symbiotic livestock. I agree with others in the hobby that patience is the key, but would add that research and learning from others' experience.