need help just starting

[seldomri]

got a 55 gallon tank and i set it all up with store bought water and salt and everything was good i took a water sample in to get tested everything was good and they said i was ready to put in some fish so i got 6 damsels to cycle the tank 2 domino black 4 striped and 2 yellow tails. is it alright to add a penquin to help the current or using a canister filter enough for a good current. the canister it for up to 55 gallon tanks. also should i use one of those air filter guys to add bubble to the tank? i tried to test the water with the hydrometer and this morning the reading was good and all of a sudden the reading jumped up on me. is this due to adding the peguin ad the air filtration into the tank? please help do not want to kill the fish. any help is greatly appriciated

[leebca]

The place you have obtained the equipment is not giving you the best advice. This is how to start up a marine aquarium: Setting Up a FOWLR Aquarium

The store doesn't understand the need to mature the tank before fishes are put in. A newly setup tank is ready for marine fishes in about 3 to 4 months.

The 55 gallon aquarium, if it is the 'show' model, is not the best choice for a marine system. It is tall and narrow which doesn't allow for the needed biological filtration. The best aquarium is one that has a large 'foot print' or one that is short but long and wide.

To best answer your questions I'd have to say follow the above procedure and stop listening to those that claim the tank is ready for fish.

For now, add nothing but clean up crew (no fish).

With regards to your equipment questions, some will be answered in the above referenced post. Ultimately you want from between 8 and 10 tank volume turnovers per hour. So if there is 50 gallons in the tank, you want flow that is between 400 and 500 gallons per hour. The flow is calculated by adding the flows of each of the inside powerheads/pumps together with the flow of any outside filters that take in and return water.

Shift in specific gravity doesn't make sense. A hydrometer is a hard-to-read and poor instrument. Many things affect its reading. Take several readings in a row to get an idea of how much it might fluctuate. If you can, upgrade to a refractometer for measuring specific gravity. Again, this information is given in the above linked reference.

You should read this post also: The Mature Aquarium

Good luck!

[metalhead]

Shift in specific gravity doesn't make sense. A hydrometer is a hard-to-read and poor instrument. Many things affect its reading. Take several readings in a row to get an idea of how much it might fluctuate. If you can, upgrade to a refractometer for measuring specific gravity. Again, this information is given in the above linked reference.

You should read this post also: The Mature Aquarium

Good luck!

Definately get a good refractometer... Well worth every penny and will make your life much easier. Keep your salinity as close to 1.025 (35ppt) as you can with as little variation as possible. FYI, do not add saltwater to replace evoparated water, use fresh RO water to replace any evaporation. You should only be adding saltwater when you do water changes and only adding the same amount of saltwater that you take out. Good Luck!