I'm used to dosing 2 part via the Neptune dose and my Alex currently fir my ca and all needs on my reefer 450. I'm setting up a new system which will be about 300g total system volume and pretty much only sps. The last thing I really need to decide on is whether I want to keep dosing 2 part or move to a calcium reactor. I feel both will have pros and cons. I'm not necessary making my decision based on costs but more which is going to have less chance for catoatrophic failure or level swings. Thanks everyone