Toxic mold growing in carpet can be worsened by fish tanks, especially if they leak.
Placing the fish tanks over a hard, cleanable surface can help control the mold.
Dehumidifiers can help, and also flow-through ventilation can help dry the area. The objective is to remove humidity and spores from the whole house, although during initial cleaning phases, it can be a good idea to keep the problem area sealed off, especially during remediation, to keep from spreading spores.
Aquarium owners should always urn a dehumidifier.
If you’re in California, you might want to give us a call and see about getting an assessment from Byebyemold.