HI there. 1/2 of 5 gal filled with fresh clean water. Will pick up dechlorinator tomorrow. Im concerned to use water from other tank since last frog in that tank died and just lost a fish recently. Other fish are healthy but I wont know if there is any bad bacteria in there. The 5 gal has a filter but it was used to house a sick fish previously and not sure how to clean it well. Stressed.. lol. Will figure it out though if it is best for Frogee for sure.