Does BB die or lose potency if there's not fish in the tank

[Alphabot]

I took a 4-month break from saltwater fish keeping and during that time around 30% of my tank's water evaporated. At the time there was no fish in the tank as I had sold them, and the only guys left were a small number of hermit crabs that I couldn't get out. I left my lights off during this time, so all my algae died too. I kept my filters running though so I was wondering now that I've returned could I just add fish in? Slowly at first obviously but I was wondering if BB could die since my salinity levels were really high. (Prior to my break the tank had been running for around 1 1/2 years.)

 

[Colin_T]

The hermit crabs should have provided enough ammonia to keep some of the filter bacteria alive. The dead/ rotting algae would also help feed the bacteria. However, the massive increase in salinity might have done some damage to the filter and probably killed the crabs.

Normally if filter bacteria is left without an ammonia source for a long time (more than a couple of weeks), the bacteria go dormant. Because the water in the tank evaporated, the salt level might have gotten too high and killed the bacteria.

I would slowly add freshwater over the course of a week to fill the tank back up. Have the lights on for 10-12 hours per day, during this time. Then check the ammonia, nitrite, nitrate, pH, etc. Then clean the filter and do a big water change. Wait a few days and add a fish. Monitor levels for a few weeks and if there is no ammonia or nitrite readings, add some more fish.

 

[PheonixKingZ]

I took a 4-month break from saltwater fish keeping and during that time around 30% of my tank's water evaporated. At the time there was no fish in the tank as I had sold them, and the only guys left were a small number of hermit crabs that I couldn't get out. I left my lights off during this time, so all my algae died too. I kept my filters running though so I was wondering now that I've returned could I just add fish in? Slowly at first obviously but I was wondering if BB could die since my salinity levels were really high. (Prior to my break the tank had been running for around 1 1/2 years.)

What are your current parameters? Salinity is going to be through the roof because of how long you've been away.

Since you onlt have hermits in there, I would add about a gallon of freshwater a day, until the tank is full again, and then measure salinity.

How big is the tank?

 

[Alphabot]

What are your current parameters? Salinity is going to be through the roof because of how long you've been away.

Since you onlt have hermits in there, I would add about a gallon of freshwater a day, until the tank is full again, and then measure salinity.

How big is the tank?

1.026, 80 gallons. I just filled it to the top with RODI water straight away.

 

[PheonixKingZ]

1.026, 80 gallons. I just filled it to the top with RODI water straight away.

Did you just test that today? Do you use a hydrometer, refractometer, or a digital tool to measure sg?