RO water leaving residue in new saltwater

[skp]

I've been using the aquarium pharmaceuticals tap water filter with instant ocean salt mix for years and ive had no major problems since my tap water tds is very low. I didnt like how it took so long to filter the water so i switched to a RO filter. Ive noticed that since i started using RO water to mix the salt, ive been getting some residue left over at the bottom which im guessing is calcium precipitate. If both my RO water and my water filtered by Aquarium pharmaceuticals tap water filter have no tds, what could be causing the residue?

any ideas?

thank you

[neanderthalman]

This is typical with IO, especially if it's an older bag. Humidity gets in the bag and precipitates the calcium before you even mix it.

 

Have you bought new salt lately?

 

 

 

Also, have you tested the TDS of your RO to ensure it's working? You didn't mix up the waste and clean water lines, did you?

[skp]

yeah i tested the ro unit and i didnt mix up the waste and clean water lines.. i have an elastic band around the waste line. The salt bucket is only 2 months old.. This problem was for sure because i changed my filter to the ro from the aquarium pharmaceuticals. I added the salt in the same way too...

I did notice that since the ro filter is much quicker the water is much colder than the water filtered with the aquarium pharmaceuticals filter. Could the water temp have an effect on this?

[AZDesertRat]

Cold water will have an effect on the salts soluability.

When you say quicker what do you mean? A 75 GPD RO or RO/DI system should make about 3 gallons per hour in perfect conditions and probably more like 2 gallons per hour with cold water and/or lower pressures.

What is the TDS or your tap and RO waters?

[skp]

My RO filter takes about an hour and 50 minutes to fill a 5 gallon bucket. The water in the bucket is still really cold when i add the salt. The aquarium pharmaceuticals tap water filter took over 10 hours to fill the bucket and the water was at room temp when i added the salt. I never tested the tds with the aquarium pharm filter but with my new ro unit i get 0 tds. My water striaght from the tap is about 9tds. I will try adding a heater to get the water to room temp before adding the salt to see if that helps. If raising the temp doesnt help then that means the ro filter is leaving something in the water that the aquarium pharmaceuticals tap water filter wasnt right?