A skimmer is a tubular device that mixes air bubbles with water, which removes both good & bad proteins from the water, bad proteins that parameter sensitive coral don't like, and it's supposed to help control nuisance algae.
You need powerheads regardless, even if you go Fish Only with no lire rock or inverts/coral. A #2 Koralia power head would be perfect for your tank to start with.
You don't exactly need a saltwater chemistry book. You need to know the basics about cycling, ammonia nitrites and nitrates. All are not good for your tank, but a cycle is something you must go through to establish your tank. If you can purchase CURED LR, along with a cup or bag of SEEDED (established) gravel, you will be GOLDEN and you may not experience a detectable cycle, or if you do - the cycling process will be sped up greatly and will only require a small water change upon completion. You also need a hydrometer like ToeJam mentioned, but you can get a LAB quality hydrometer that looks like a giant Thermometer. These are used to calibrate Refractometers that everyone raves about, yet they are under $15 bucks and once you read the directions, they are REALLY easy to use & understand! You should have an extra power head on hand to stick in the bucket to mix up your water, along with a spare heater to match the water temperature!
You CAN use tap water. I know several people in my area that use tap water with LPS and some SPS, with good equipment and have no algae issues or growth issues. I started my tank using tap water and within days I have a Diatom outbreak and chose to just do it the fail-safe way and switch to RO/DI water, especially since I'm new to the hobby and don't know all the tell tale signs of trouble or future problems! My local tap water happens to contain no phosphates or nitrates, no copper or iron is detectable, but I'm playing it safe from here on out. It's been roughly 5 weeks of 5g water changes, so I think I'm tap water free now.
You need powerheads regardless, even if you go Fish Only with no lire rock or inverts/coral. A #2 Koralia power head would be perfect for your tank to start with.
You don't exactly need a saltwater chemistry book. You need to know the basics about cycling, ammonia nitrites and nitrates. All are not good for your tank, but a cycle is something you must go through to establish your tank. If you can purchase CURED LR, along with a cup or bag of SEEDED (established) gravel, you will be GOLDEN and you may not experience a detectable cycle, or if you do - the cycling process will be sped up greatly and will only require a small water change upon completion. You also need a hydrometer like ToeJam mentioned, but you can get a LAB quality hydrometer that looks like a giant Thermometer. These are used to calibrate Refractometers that everyone raves about, yet they are under $15 bucks and once you read the directions, they are REALLY easy to use & understand! You should have an extra power head on hand to stick in the bucket to mix up your water, along with a spare heater to match the water temperature!
You CAN use tap water. I know several people in my area that use tap water with LPS and some SPS, with good equipment and have no algae issues or growth issues. I started my tank using tap water and within days I have a Diatom outbreak and chose to just do it the fail-safe way and switch to RO/DI water, especially since I'm new to the hobby and don't know all the tell tale signs of trouble or future problems! My local tap water happens to contain no phosphates or nitrates, no copper or iron is detectable, but I'm playing it safe from here on out. It's been roughly 5 weeks of 5g water changes, so I think I'm tap water free now.