Water Top Off

[jackalexander]

My salinity is rising slowly rising and I don’t have an RODI system. I do have an RO system that I drink from but I was told that RODI is better for the fish. Any ideas what water I could use to top off my tank? (my RO has a TDS of <30).

 

[Philly Reefer]

Rodi is preferred but you can use that RO water still. 30 TDS is not bad. But if you are seeing more algae in the future, at least you know why.

The best advised I received when I started this saltwater hobby(3months ago) was to get ATO system 1st. Takes out the chore of topping off water. Oo and Rodi system of course

 

[BlennyTime]

BRS sells a DI chamber you can add to your RO system, if interested.

Single Deionization Canister with DM-1 Dual TDS Meter

Single deionization add on canister kit complete with Dual TDS Meter and pre-packed color changing DI cartridges! Dimensions - 14" x 6" x 5.5" Dual TDS Meter already installed Perfect for adding additional DI stages to your RO system Cartridges come with canisters full of Color Changing DI...

www.bulkreefsupply.com

 

[Jib]

My LFS sells RODI for 50 cents per gallon. Perhaps your LFS does too? I have a small tank so this is the approach I have taken. May not be as feasible for you depending on tank size.

 

[PatW]

A 30 TDS out of an RO membrane is pretty high. You might be starting out with really high TDS tap water. An RO membrane should have a 98% rejection rate. So 100 TDS source water will yield 2 TDS post membrane. I think that your current system really is not up to par. The most expensive supply in an RODI system is the deionization resin so you want to lower the consumption as much as possible. There are a fair number of venders selling decent RO systems and most of the starter systems are reasonably priced.

For most reefers, getting an RODI system makes sense. 1) You get 0 TDS water. That pretty much eliminates problems of heavy metals and contaminants in your source water. 2) You know the quality of your water. If you buy from a store, you really do not know their quality control. 3) You do not have to go to the store, buy water, and haul it back home. 4) It is easy to have a tub of water and a tub mixed up salt water on hand. These things come in handy. 5) If your system is of any size, your savings on the production of the water will pay for you system in pretty short order.