Maintaining salinity is relatively easy when it comes to tanks with less advanced stock. In this article, I will briefly describe in a few points how to keep salinity stable at the beginners’ level.

If you’d like to learn more about salinity, I described it in this article: What is salinity?

A few simple rules:

1. Replenish evaporated water with fresh RO water (salt doesn’t evaporate).
2. Adjust the salinity when mixing new saltwater so that the new brine has the same salinity as the aquarium water. It’s crucial that the added water also has the same temperature. This is very important because salinity changes with temperature.
3. Make one-to-one water changes, that is, as much water as you drain, you add to the aquarium.
4. If you are dosing mineral supplements, remember that two- or one-bottle components will increase salinity over time. So it’s worth using solutions that contain a complete set of minerals, including salt without salt. Otherwise, you’ll have to do a big water change to get back on track.
5. When you take out water to acclimatize fish or corals, remember to add the same amount of saltwater to the aquarium.
6. A wet skimmer can cause the salt level to slowly decline. If we remove a cup full of brine from the aquarium, we should also replenish the same amount of circulating seawater.
7. If you measure salinity and you find that there’s been a change, first check the measurement again. If the salinity has really changed for some reason, then if you want to increase it, do it slowly.

If we act carefully and know the proper rules, we will easily keep the salinity in our aquarium at the right level.