Question About RO/DI Filter

[Cetus]

So, I'm setting up a 125 gallon tank and I had a question regarding the RO/DI filters GPD. I can't find a filter with exactly 125 GPD but is that really necessary? I would think that outside of totally replacing the tank water, that I can get away with maybe 75 GPD for a tank like this? But I'm not sure if there are specific things that make having a GPD equal to or higher than the tanks capacity is advisable. So, what should I look for here?

 

[Reef - Tripp]

The ro/di filter is only for the water that you use to prepare new water or to replace the evaporated water, it does not have to do with the size of the system

 

[Reef.]

So, I'm setting up a 125 gallon tank and I had a question regarding the RO/DI filters GPD. I can't find a filter with exactly 125 GPD but is that really necessary? I would think that outside of totally replacing the tank water, that I can get away with maybe 75 GPD for a tank like this? But I'm not sure if there are specific things that make having a GPD equal to or higher than the tanks capacity is advisable. So, what should I look for here?

the 125 size thing is only telling you the speed it makes water, for a 50 will make 50 gallons in 24 hours etc, if you don’t mind waiting buy whichever you want, but keep in mind that if your water pressure is not quite high, you will probably not get the stated output.

also the membrane which gives the unit its output can be increased, so you could buy a 100, then when you change it, swap to a 125 with a new flow restrict or too.