titch 104 Posted May 14, 2017 2 minutes ago, koko said: We are going to do it like we did last time hun but for a month Ok. Last time I made a batch up & kept it in the fridge, replacing what I took out with that. But I knew what volume of water I was going to be changing each time & how often, so I could calculate it all. This time I don't, right? Because of the fish-in cycle I could be changing X litres one day and Y litres another, and not at regular intervals. So can I just redose with fresh FS each time, replacing what I've removed? 0 Quote Share this post Link to post Share on other sites