Hikari® Aquarium Solutions® AccuProbe™ Hydrometer Bulk That would translate to 13

That would translate to 13 to 32 liters of air per minute per foot of tubing

and it will bond to liner

*Feeding should be carefully regulated based on Koi activity level

000 gallons for 16 months BMC1G4 097121201355 128oz (Gallon) Bulk/Refill Size

Hikari® Aquarium Solutions® AccuProbe™ Hydrometer Bulk That would translate to 13The Hikari Aquarium Solutions AccuProbe Hydrometer measures a wide range of specific gravity and is intended for marine aquarium use. "Dry hands" design avoids contamination of aquarium Measures a water sample at 6" depth to avoid inaccurate surface sampling Accurate to 0. 001 specific gravity and salinity Designed to give a temperature corrected reading in warm water aquariums Durable construction for extended life Includes self leveling hanging