Reefs.org Forums

[weissgarber]

I have a 56 gallon reef tank and I am using tap water which measures 243 ppm on a TDS meter I purchased. Is that too high to use with a salt mix? I seem to get a film on top of the water a lot and fear the tap water may be causing it. I am probably going to purchase an RO. I do have an in-line filter system on my water main (charcoal and sedement) which helps the water quality a bit but I do fear it is not enough and may be the cause of my algae issues in my tank. What is a good number for tap water prior to adding reef salt?

[Ben]

I personally do not see a reason to use tap in a reef tank. When I am spending good money on GFO and carbon, etc..I dont want to be throwing that away by then doing top off and water changes with tap. RO/DI filters are not that expensive upfront but in the long run, they are very cheap. I use my RO/DI for the reef tank, and splice the RO section off to my fridge for my fridge water and ice maker. Makes everyone happy.

As for the film on the surface, do you have a sump? What do you do for circulation. In some cases even with the good circulation the planning of it doesn't always allow the surface slick to go over the overflow. If you have a sump then try re-aligning the circulation in the tank so the slick goes down the overflow. If you have no sump, point some wide angled powerheads, at the surface to create more surface movement.

[AZDesertRat]

There is no good TDS in tap water. Your goal is always 0 TDS as the things you do want in your system are contained in a good salt mix.