RO vs. Tap water??

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Aquarium Advice Regular
Sep 24, 2003
Jackson Ms
I set my new 150 up about a week ago. I have been letting it run for a while with water in it. I ordered rock from this past wednesday. I got an email from them today with shipment info and saying that I needed to make sure I set the tank up with RO water not tap water. I know most people use RO but I did not realize it was necessary. What will happen if it set up with tap water? Will my tap water kill all my little creatures that come in on the LR? LR is suppose to be here wednesday I can do a change this weekend if I need to.
Tap water really varies from place to place. Depends if it is city water, well water... Generally speaking, tap water is not great for aquariums because it contains chemicals and heavey metals. An ro/di unit will take out 99.9% of impurities. Tap water can be high in nitrates, phosphates and other stuff that lead to poor water quality issues. If this is a FOWLR tank you may b able to get started with tap water but it is not the best method. If you plan on having a reef RO water will be a must. Most LFS sell RO/DI water or you can find it at the "self-serve" joints like Wal-Mart or the grocery store.
I had no idea RO was so important. I already got an email back from Mike at, it convinced me to go ahead and change the water out. I'm heading out to walmart and the grocery store to get some water.
Hate I wasted one of those huge buckets of salt. Oh well.
Speaking of RO water. Has anyone experienced a rise in PH with Ro over tap? My tap has always been low 7's for PH. I did a water change last night and tested the PH from my RO and found it to be in the low to mid 8's. Tested it 4 times to be sure. Can't figure that one out at all.
For the reasons lando stated Ro or ro/di is a must have. I know people who use tap and are still battling algae problems even after they made the switch to better water.
SW is not a cheap hobby and the most important item is WATER so don't go cheap here, IMO it could cost you more money in the long run.
I'm going to get some RO for my tank. My delima now, is for what I'll pay for 180 gallons of RO water and some big tubs to transport it in I could nearly pay for a RO unit off of ebay, but if I purchase one off of ebay I know it wont be here set up with enough water by wens when the rock arrives. I know we will be moving probably with in a year, are the RO units easy to remove and relocate?

Would it be horrible to go ahead and put my LR in the tank with the running tap water, and do some large water changes as soon as the RO unit gets here?
A RO/DI unit is small, most can fit under a sink. How much LR are you getting?
You can pick up a couple garbage cans and fill them with the SW from your tank and then place the LR in them till you get your RO unit. You will need a PH in each can u use. You can also do what you want but IMO it could be some time till you do enough water changes to get all the tap water out. There are people who have tap water that is fine to use and they never have any problems. There are others when you listen to there stories it can give you nightmares. Its a crap shoot could work out fine or it may give you problems. Adding the LR to the tank as it is IMO will not kill the LR and make it useless. Its a tuff call, what ever you do just don't leave the LR out of water for too long after you get it.
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