What are these tiny white bugs in my frog tank and how to remove them?

Identification is difficult since they are so tiny and not clear in the images provided. They may have come in on substrate or plants. You can clean and sanitize the tank and bowls then replace the substrate and plants. That may solve the infestation. Monitor humidity and temp. Both are important for Billie, but both can also foster pests, bacteria and mold.

Without a close up image, it is difficult to determine what these dots are. They could be springtail mites. These are harmless mites that feed on decaying matter. High humidity levels and a food source draw them in. They may have hitched a ride in on the live food or new fat tails you acquired. Treatment involves removing food sources, decreasing humidity and sanitizing cages, bowls, etc. Soaking your affected geckos in water may clean them off.

They are probably springtails. It is likely they came in on the plants or wood. They aren't harmful, but can be unsightly in large numbers. In bioactive tanks, they are used as "janitors" to clean up decaying matter, uneaten food and feces.

It looks like a fish louse. They aren't actual lice, but tiny little crustaceans. You'll need to treat the entire tank. These little buggers can be introduced to your tank on new fish or live plants. Microbe-Lift Fish Lice & Anchor Worm treatment is the recommended treatment of choice. Follow label directions carefully.

Remove her from her main tank and put her in a smaller hospital tank. You can use paper towels for substrate. Change them daily. Increase tank temps to 80 F with a basking spot of about 85 F. Maintain humidity at 70%. Mist her daily and provide a water bowl. Use only dechlorinated water. It she isn't defecating normally, a soak in a honey and water solution may stimulate defecation. A dilute unflavored PediaLyte solution can treat or prevent mild dehydration. Offer appropriately sized prey, no bigger than the space between her eyes. You can also feed bits of nightcrawlers. If the redness and symptoms persist, have her examined by your veterinarian or a vet experienced in treating reptiles and amphibians.

Clean and sanitize the tank. Replace ALL the substrate with fresh organic topsoil or coco fiber. Do not use vermiculite or perlite. Avoid gravel, sand or wood chips. Ideal temperature ranges between 68F and 78F with the cooler end reserved for nighttime. Mist the cage several times weekly to maintain humidity. Provide a water bowl and clean it daily. Soak him in a tepid (75F) 50/50 solution of water and unflavored PediaLyte. This will provide warmth and hydration. A cold frog will not eat. Afterwards, offer live food. Something with a lot of movement like nightcrawlers or mealworms. If he still doesn't eat, have him examined by your veterinarian or a vet experienced in treating reptiles and amphibians.

Maintain pristine water quality in the main tank and monitor the fish for similar symptoms. A bit of aquarium salt ( not table or Epsom salt) can be used as a general tonic to reduce stress, improve gill function, treat minor infection and aid in recovery. Dissolve 1 teaspoon of salt per gallon of water in a cup or two of tank water and gently pour it into the tank. Treat for no more than two weeks then perform partial water changes to decrease salinity. Use only conditioned water that is temperature matched to prevent stress or shock. I am sorry for the loss of your frog. Your remaining ADF sounds quite ill by your description. Again, maintain pristine water quality in the quarantine tank with a water temp of 78 F. ADFs, and amphibians in general, ate quite sensitive to changes in water chemistry. Elevated ammonia or nitrite levels can kill. Other possibilities for the bloating include improper diet, obstruction or kidney failure. You can try a fast for a couple days along with salt baths. This may relieve the bloating. If it is dropsy, unfortunately by the time a frog is bloated, the survival rate is very low.