New 55g, RO/DI water questions

[sosgal721]

I am setting up a 55g tank in within the next week and I had some questions about using RO/DI water. Until now my fish have been in a 20g and I have been using tap water for everything since it already has a ph of 7.9. I plan to use only RO/DI water in the 55g and would like to know what I need to add back into the water to replace what was removed by the RO/DI unit? The tank will be a FOWLR and have various inverts.

Also, I have read a lot about how inaccurate hydrometers are and was wondering if I need to get a refractometer. As mentioned above there won't be anything but fish and inverts unless they come in on the LR, so I'm not sure how precise I need to be.

[Reefscape]

there is nothing that you should need to add back to the tank if you use a good salt like reef crystals....

Get a refractometer, they are far far better than a hydrometer and are worth spending the extra on them....

Niko

[Pallen81]

:iagree:

if you don't use Reef Crystals, make sure to buffer the RO water with some marine pH buffer.

the Refractometer will last you pretty much forever if you clean it after use and don't drop it. i got one and its super sterdy and reliable.

[sosgal721]

Thanks for the quick replies. I have read various posts that mention adding calcium, iodine, or various minerals that are in tap water, so I wasn't sure if that was necessary, especially when replacing evaporated water between changes.

if you don't use Reef Crystals, make sure to buffer the RO water with some marine pH buffer.

I have about 100 gallons worth of Instant Ocean sea salt, so is that considered good? If it is good and I use it will I need to buffer the water first? I did a test a week ago on some RO water that I get from WalMart for the freshwater tank and adding salt makes the ph go from low 6's to low 8's.

[Pallen81]

I have about 100 gallons worth of Instant Ocean sea salt, so is that considered good? If it is good and I use it will I need to buffer the water first? I did a test a week ago on some RO water that I get from WalMart for the freshwater tank and adding salt makes the ph go from low 6's to low 8's.

I was using instant ocean and had to supplement the pH with a marine buffer. Instant Ocean got my water to around 7.8-8.0 area. so just to be sure I added some buffer to help increase the alkalinity as well as the pH.

I know use Reef Crystals at the moment.