But don’t add to much fresh water at any one time because if you do, you may cause both beads to sink to the bottom of your Sea-O-Wonders which means that that now you have added to much water! If you always fill your Instant Sea-O-Wonders to the exact same level every time you top up with pure water this shall never happen. 

Ok so what if I have added to much water? 
Again it is easy. You could either leave the cover of your aquarium off which unfortunately does take some time or to speed things up you could (with the help of parents kids) position a small electric fan close by to blow across the water’s surface which will rapidly hasten evaporation and reduce the water level quickly. 

What to watch out for.

As the water begins to disappear so to does the salt concentration of your Instant Sea-O-Wonders get stronger. Eventually when the water reaches its correct concentration of salt, one bead will be floating again and one will be sitting on the bottom. 

Want to learn more? 

These beads are in fact a very simple form of hydrometer which is can accurately measure the salt concentration in marine and reef aquariums by expert hobbyists.