Use a Fish Tank to Discuss Conversions: Gallons to Litres to OuncesUse a fish tank to learn about conversions from gallons to litres, litres to cups, and more. Photo SourceShare this:Share this: Share Use a Fish Tank to Discuss Conversions: Gallons to Litres to Ounces on Facebook Share Use a Fish Tank to Discuss Conversions: Gallons to Litres to Ounces on Twitter Share Use a Fish Tank to Discuss Conversions: Gallons to Litres to Ounces on Pinterest Share Use a Fish Tank to Discuss Conversions: Gallons to Litres to Ounces by Email