Some cameras have Kelvin settings if you know what's the colour temperature. However, most of the time you not only have that lightings but also those of ambient. As such, if your camera has Preset WB settings that would be great. Use that to take a white object as a preset so that the camera will remove that colour cast each time a photo is taken. When you do this, there is no need to edit your photos to adjust WB. You can even shoot them in JPG instead of RAW to save space.
To illustrate with a PnS camera:
JPG Photo taken using Auto-WB (It will look blueish because of your blue lights)
Same JPG photo taken using WB Presets (No editing. It will immediately remove the colour cast. You don't see the blues that much and actually you see warm white lightings that I use)
Don't use flash unless your flashes are coming from the top of the tank (wireless remote)
If you think your photos are under-exposed, use exposure compensation. In these case, I used +2/3EV. You may also do exposure correction when you edit, your choice.
Hope that helps. Cheers!