RO/DI systems
- Thread starter MIKE D
- Start date
Catpicklesdog
Hindsight is a wonderful thing!
IMO they're definately worth it. I'd been in this hobby for 3 years before I got one and now I wonder how I ever managed without one. Quite often I'll have a container of water ready in case of emergency or just a routine water change. If you can I'd start as you mean to go on and start with RO water. I know a lot of people do use well water but I'd test it first.
I feel a RO/DI unit is worth it for any sw tank. Using water of that purity to mix saltwater greatly reduces the likelihood of nuissance algae for the vast majority of us. Yes, there are certain places where municipal tap water or well water are perfectly fine to use as they are, but most of us don't live in those areas. Having your water tested is the easiest way to find out.
Being on a well, there are some additional things to consider as you look into buying a RO/DI unit. Water pressure is a big one. If you don't have a high enough water pressure, the RO/DI unit will operate far below its rated output and you'll generate a lot more waste water than if the water pressure is in the recommended operating range. The second thing to look into is the CO2 concetration of your well water. I didn't know this was such an issue, but a friend of ours found this out when he installed a RO/DI unit on their well. If there's excessive CO2 in the well water, it will burn through an entire DI resin cartridge within the first several gallons of water that's run through the cartridge. Our friend has this problem, so he ended up removing the DI cartridge after it completely changed color within an hour of its first use and simply uses the unit to make RO water for his reef tank. I don't remember all the chemistry behind why this happens, but he was made aware of this possibility from the vendor he bought their RO/DI unit from (thefilterguys.biz), tested his well water for CO2, found out it was borderline high, gave it a try, and discovered he'd have this issue with DI cartridges. There are ways to work around it, but they are pretty time consuming, require some extra steps, more equipment, more storage capacity (only to make the extra steps a bit more conveinent), and our friend decided the extra work was too much effort. His tank has been running fine on just RO filtration for almost a year now, but well water quality does vary from place to place and even over time within a particular well.
Being on a well, there are some additional things to consider as you look into buying a RO/DI unit. Water pressure is a big one. If you don't have a high enough water pressure, the RO/DI unit will operate far below its rated output and you'll generate a lot more waste water than if the water pressure is in the recommended operating range. The second thing to look into is the CO2 concetration of your well water. I didn't know this was such an issue, but a friend of ours found this out when he installed a RO/DI unit on their well. If there's excessive CO2 in the well water, it will burn through an entire DI resin cartridge within the first several gallons of water that's run through the cartridge. Our friend has this problem, so he ended up removing the DI cartridge after it completely changed color within an hour of its first use and simply uses the unit to make RO water for his reef tank. I don't remember all the chemistry behind why this happens, but he was made aware of this possibility from the vendor he bought their RO/DI unit from (thefilterguys.biz), tested his well water for CO2, found out it was borderline high, gave it a try, and discovered he'd have this issue with DI cartridges. There are ways to work around it, but they are pretty time consuming, require some extra steps, more equipment, more storage capacity (only to make the extra steps a bit more conveinent), and our friend decided the extra work was too much effort. His tank has been running fine on just RO filtration for almost a year now, but well water quality does vary from place to place and even over time within a particular well.
I would never start a tank without one after my previous experiences.. Water quality is the #1 thing we strive for in the salty world..