Rodi water change made Algie change colour

[derrick719]

Hello I bought an ro di water filter as my place is on a well.
I used it for the first time and it change the red Algie in my tank green. Is this normal
I've been using bottles of ro water before

[BlueTang<3]

I have no experience with using well water, how old is your tank? did it switch colour almost immediately or slowly could be a coincidence and a stage of the algae? Did u check the tds coming out for your water ? Did u purchase a new unit or used? I am thinking that being well water it may not be at zero. May also have something to do with other things in your water vs bought water, iron comes to mind but should all be removed assuming filters are ok. Found this interesting read.

http://www.reefcentral.com/index.php/rodi-faq
What if I have well water?

Well water is free of chlorine, so you don't need to worry about it attacking your RO membrane. Do not buy a CTA membrane if you have well water, as bacteria will be prone to destroy it. A carbon block is not needed for well water, but well water often contains higher levels of particulate matter than treated water. Consider adding a second particulate filter instead of the carbon block. If your well is prone to "red" water problems due to iron bacteria, a back-flush option will help reduce membrane fouling.

[derrick719]

It changed over time and this morning I had a nitrate spike and killed a few fish.
The Rodi is brand new and have never used one before I think I may have had to run it for a bit first. I don't know where I would go to test the water. I just have the nitrates and ammonia testers

[hillegom]

Yes, you should discard at least the first 5 gal of water. I was told there is some kind of preservative to keep the filters from growing bacteria.