First off all, when doing a water change do you need to have the salt water mixed up and ready in advance in a bucket somewhere? I keep hearing about tap water top offs, is this replacing evaporated tank saltwater with chlorinated tap water? this is what i did with fresh water tanks to keep the water level up, but i never imagined doing in in a fragile saltwater tank

It is best to mix your salwater a few days in advance while keeping it circulated with a power head and heater to keep the temp at around 78 degrees. Ikeep mine going in a Brute trash container. Also, in a saltwater tank the freshwater will evaporate from the saltwater you will notice this by a drop in water level. Mine drops a 1/2" to 1" a day so every day i fill with freshwater (RODI) to bring up to normal water level.

what is RODI?

reverse osmosis/di ionized water do not use regular tap water. Use water that has gone through a filtering process usually found at the outside of supermarkets.

Check your LFS as well for RO water, it is often cheaper then the supermarket water.

Hooking up an ATO (automatic top off) to your wet/dry / sump is a great idea. I like the Kent float valve drilled through the side. When I worked at the aquarium store many years ago, we used toilet tank float valves on a U made from pvc pipe, and didnt drill the sumps. There are many ways to do this. There's also electronic water level devices that'lll kick on a pump to fill when water level is low, and you can configure it those systems to also shut of your main pump if the water level gets way too low.

Nope. But some do to make sure all the salt has dissolved.Yep (with whatever tap water you have. I presume you are not adding chlorine.)A marine fish and soft coral tank will do fine with tap water top offs which are frequent. Especially if the tank is balanced out and maintained with macro algaes. SPS corals are more sensitive and possibily ro/di top off would be recommended.


For tank where you do regular water changes the you may want to use ro/di even for the soft corals. Because the tank conditions are more dependant on the conditions of the replacement water.



my .02

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden