3a : to place or invest in such a manner as to make unavailable for other purposes their money was tied up in stocksb : to restrain from normal movement, operation, or progress traffic was tied up for miles. 4a : to keep busy was tied up in conference all dayb : to preempt the use of tied up the phone for an hour.
A 20-gallon tank is the minimum tank size for a reef or saltwater tank. Although it may be harder to maintain than a bigger tank, it is possible to create a saltwater tank using 20 gallons. Be mindful of the fish stocking to ensure that too many fish do not over-pollute the system.
Each gallon of sea water contains about 4.5 ounces of salt, which is about 3.5 percent of its total weight. A cubic foot of salt water weighs about 64 pounds. Because salt water is heavier, it is able to buoy objects up with a greater force, so objects float slightly better in salt water. Learn more about Measurements