Setting up a 55-gallon tank: How much substrate for a 3-inch bed?

Our Standard Aquarium Plant Pack provides a convenient solution for your dilemma. This package includes Micro Sword or Dwarf Hairgrass, Anubias Nana or Anubias Barteri Round Leaf, Java Fern, Red Cryptocoryne or Green Cryptocoryne, Water Sprite, Hornwort, and Cabomba. http://www.liveaquaria.com/product/prod_display.cfm?c=768+2145+2146&pcatid=2146 A substrate specifically designed for live aquarium plants such as CaribSea Eco-Complete Plant Substrate is recommended for long-term success. http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=9087 Be sure to provide proper lighting conditions by employing aquarium light fixtures specifically designed for planted aquarium use.

That's terrific news! It is great to read of your frog's recovery. Most keepers will keep a bare bottom tank. This will prevent ingestion of substrate and makes finding food easier for the frogs. It also makes it easier to keep the tank clean. Sand would be fine. If they inadvertently ingest some, it should pass easily. If you decide on gravel or river rock, make sure it it large enough to prevent ingestion.

If you are referring to Mystery Snails, then 3 or 4 would be fine for that size tank. Some aquarists may recommend 1-2 snails per 5 gallons, but it depends on what else you plan on keeping in the tank.

A 55 gallon tank is truly not large enough for an Oscar. Usually they are housed singly or in a mated pair. A single adult Oscar should have around a 75 gallon tank MINIMUM and a pair needs 100G or larger. Here's a bit more info on Oscars https://www.petcoach.co/article/oscar/

You can, however it isn't as simple as collecting a few bucketsful and dumping them in your tank. You will need to properly clean the sand to remove impurities and parasites. This involves soaking the sand, water changes, more soaking amd more water changes. It may take several weeks. There are videos you can watch on the bigger video hosting sites. It is much easier, and safer for your fish, to buy sand that has been prepared already.

Choose the largest cage your space and budget will allow. At minimum, a 55 gallon enclosure should be considered. Acceptable substrates include slate, reptile carpet, decomposed granite or large gravel. Yes, setting up a bio-active environment for beardies is possible. It will take a bit of research and effort to get it right.

The rule of thumb is 1.5" of fish per gallon of tank. So estimate the length of each fish you have, add them all and divide by 1.5. This will give you the size tank you will need in gallons. In a 30 gallon tank you can keep 45 inches of fish (i,e, 45 fish, each 1 " long or 30 fish , each 1.5" long, etc. Do not forget to leave some space for growth of fish.