Hi Katrina71, I run a small Pico tank 19L, about 5 us Gal, had it running for about 9 months. There are many different methods to running a reef aquarium. As you seem new to saltwater aquariums, I would strongly suggest you purchase a good book to learn the basics of keeping a marine aquarium. Try to be patient, better to reduce the number of common mistakes usually associated with starting such a project. Don`t` get bogged down in the technical aspects such as sterilisztion and protien skimming. Try to keep things simple. First study the basic chemistry and biology involved in starting the aquarium and maintaining the biological filtration (Nitrogen Cycle).
One of the problems that puts of many a new reefer is the biological battle that takes off before your tank becomes mature. Diatoms, unsightly Algae, Cyano Dino bacteria, all fighting for dominance . This is the natural process that signifies your aquarium is becoming a living community of diverse organisms. This process can become a problem if you don`t` keep things in balance. This is one of the reasons I suggest you keep things simple to start and build up slowly as the tank matures.
With regards rock and sand, Think carefully about how you eventually want your aquarium to look in the future and plan accordingly, the less you keep changing and disturbing your tank the quicker it will mature. Don`t` be tempted to try and make your aquarium look like the pictures in the magazines within a few months. Its very tempting once your aquarium is cycled to buy all those great looking corals and animals to fill your tank. But inevitably this will put a great strain on the balance you are aiming for.
Equipment I would recommend are:
A heater with a separate heating control unit to overcome the chances of your tank quickly overheating in the case of thermostat failure.
A small pump to give circulation within the tanks filtration and provide a little agitation to the surface enabling gas exchange.
For biological filtration, go with some quality man made substance such as Marine Pure or equivalent. This will reduce the amount of rock required in the DT and enable better choices for aquascapeing and water flow.
For mechanichal filtration a simple hang on filter would suffice if the tank has no rear sump. Get one large enough to contain your biological media and chemical filtration Phos remover and Carbon, such as Chemipure.
For rock I would go with artificial rock designed for a marine aquarium, such as Reel Reef Rock or similar. Live rock and dead reef rock would have a potential to increase levels of Phosphates and Nitrates as they mature.
Choice of sand is down to personal preference as to how you want your tank to look. I would suggest a shallow sand bed is easier for the beginner to maintain.
A small lighting unit preferably one with a dominance in the blue spectrum. Freshwater aquarium lights tend to be dominant in the green and red spectrum and may encourage the growth of unsightly Algae.
An Automatic Top Off unit that replaces any evaporated water and maintains a stable salinity. This reduces the need for continuous monitoring and top ups with RODI water.
May I suggest you start with some small animals such as small ornamental shrimp as your first inhabitants. These animals require very little additional feeding and will scavenge detritus and other particles. They are also a good indicator of water quality as they can be sensitive to sudden changes within the water chemistry. In my experience an addition of small animals such as amphipods and copepods make a great clean up crew in a Pico. The usual animals associated with clean up crew, such as snails may find it difficult to find sufficient food source in such a small system and Hermit Crabs may pose a threat to any of the small animals that will be suitable inhabitants for such a small space.
I think it may be wise to wait on any corals or Macro Algaes until you have gained some experience of running your system. The main reason for this is photosynthetic animals require specific lighting intensity and spectrum. This would be one of the biggest factors in rapidly increasing any unwanted algae growth within the tank. For nutrient control, better to start with reducing the amount of nutrients that you place in the tank in the way of food and carrying out regular small water changes. This is one of the beauties of a Pico tank you can easily change a little water just using a small plastic cup.
Last but not least enjoy your little marine world and take good care of your animals. I have enclosed a pictures of one of my Five , Thor Ambionensis, (Sexy Shrimp) which inhabit my Pico tank along with my Pom Pom Crab.
Please support sustainable practices within our Hobby. Tony Thompson.