I've had an Octo 3K for about 7 years. I also have had an AquacontrollerPro for the past 2 years. The Octo is a good controller. Personally, I have found it more stable and less prone to interference and general "flakiness" compared to my ACPro. It has an internal battery backed clock which means that it never loses the date/time. My ACPro does occasionally reset the clock even with the external battery backup. I've never has ANY interference on my Octo.....not on pH, ORP, temp, or conductivity. The unit has been 100% rock solid from that standpoint.
Having said that, the Octo doesn't seem to be as popular. Probably several reasons for this.
Aquadyne customer support is not that great. Thankfully, I've rarely needed it since the unit is so solid. If you look around there are forums for Neptune and the Aquatronica.
It has a rigidly structure setpoint system which means less flexibility. It is easier to set up and a little more "idiot proof", but you do sacrifice the flexibility that you can have with the "scripting" style setpoints that the Neptune controllers have. Not really sure how the Aquatronica compares.
You are pretty much stuck with X10 to control things. Aquadyne's website lists a relay control system (RCS) for use with their high end controllers (Aquanode series), but don't lists prices or indicate that it can be used with the Octopus controller. Neptune has their Direct Connect boxes and Aquatronica has their powerbars. Both can have problems as evidenced in the forums, but X10 is not an option for some people.
Aquadyne doesn't really seem to be trying to innovate or advance their product. I looked at the specs for the new Octo 4K, and I didn't see anything new. It looks like they put a new faceplate on the 3K. They just don't seem to be interested in keeping up with the Aquacontroller and the Aquatronica as far as features. Maybe they are concentrating on their higher end units which are marketed towards public aquariums and aquaculture. I've also noticed that it is harder and harder to find vendors who carry the Aquadyne products. Aquatic Ecosystems doesn't even carry them any more. It's a shame really. From an engineering/electrical sense, I've found the unit to be rock solid.
Hope the info helps.,
Michael
