[Myka]

When I used H2Ocean I would lower the alkalinity using muriatic acid prior to doing water changes. Be aware that it DRAMATICALLY lowers pH for several hours because the reaction creates CO2. pH will rise back up, but you can't use the water for several hours. Muriatic acids only affects alkalinity and pH.

My buckets of H2Ocean would start around 9.0 dKH, I added 7 mL muriatic acid to 17 gallons of saltwater, and that lowered the alkalinity to about 7.5 dKH. I would suggest you test alkalinity, add a half dose, wait an hour, test again, and see how much more you need to add. Do you have a digital pH meter? You should check pH before adding livestock to the tank as will probably be down in the 6's after you dose. Don't bother with a pH test kit though - it's not good enough. Just make sure the water is in the high 7's before you add livestock.

Btw, provided you don't grossly overdose, it won't hurt your equipment. You won't actually see any changes visually. As mentioned though, it will produce a small whiff of vapor when you open the bottle and also when you add it to the tank - don't breathe it. If you open the windows in the house it will help bring the pH up and will clear that vapor quick too. If you point the powerheads towards the water surface that will help bring the pH up faster too by helping to off-gas the CO2.