It depends on how you plan to use them—top dressing, drainage, or semi-hydro growing.

• Smooth river rocks: Great for a clean, finished look on top of soil and to help reduce splash when watering. Medium sizes (around 3/8–3/4 in, as listed on some items) suit most planters.
• Lava rock: Lightweight and porous, which can support airflow around roots. Popular around cacti, succulents, and bonsai.
• Expanded clay pebbles (LECA): Ideal for hydroponic or semi-hydro setups and as an aeration layer in pots.
• Decorative chips or crystals: Best used as accent layers in small areas or terrariums.

Whatever you choose, keep drainage holes clear and avoid burying stems to promote healthy airflow.

Coverage can vary by pebble size and pot shape, so a quick at-home estimate helps.

1. Measure your pot: Note the top diameter to gauge the surface you want to cover.
2. Decide on layer thickness: Many people use about a 1-inch top layer for a tidy finish; drainage layers at the bottom are typically thinner.
3. Test the volume: Add pebbles from a measuring cup to an empty pot of similar size to see how many cups you’ll need.

Rocks are sold by weight or volume, so check the product details for bag size. Buying a little extra can help account for differences in stone shape. Pickup or delivery options at checkout can make topping off easy.

Some rocks on this page are labeled for fish tanks, while others are for decor or landscaping. If you’re setting up an aquarium:

• Look for aquarium-friendly wording: Check product titles and descriptions for mentions like “aquarium,” “fish tank,” or “terrarium.”
• Rinse thoroughly: A gentle rinse can help remove dust before adding to your tank.
• Consider water chemistry: Certain stones may influence pH or hardness. Research your species’ needs and review product details.
• Check edges and coatings: Smooth, natural river rocks are often preferred; avoid sharp edges and items with dyes or finishes not noted for aquarium use.

When unsure, start with a small test or consult aquarium care resources for your setup.

Yes—choose lava rock that’s specifically labeled for natural gas or propane fire pits. That product detail indicates it’s suited for high heat.

• Use dry rock only: Moisture can cause popping under heat.
• Follow your fire pit’s instructions: Place rocks as directed so burner ports aren’t obstructed.
• Avoid non-heat-rated stones: Don’t use polished or decorative pebbles not intended for fire features.
• Allow to cool before handling: Rocks retain heat and can be very hot after use.

Arrangement and performance can vary by pit design, so check the owner’s manual for fill depth and maintenance recommendations.

If you’re keeping costs in check, versatile options often include mixed-color river rocks or pea-sized stones, since they cover ground well and work across beds, borders, and planters.

• Choose practical sizes: Medium pebbles (roughly 3/8–1 in) typically provide good coverage without sinking too deeply.
• Buy efficient quantities: Multi-pound or multi-bag options can be helpful for larger areas.
• Use accents strategically: Save specialty stones or glow pebbles for focal points and fill the rest with broader-coverage rock.
• Plan your mix: Combining rock with mulch in low-traffic zones can reduce the total rock needed.

Use the page filters to compare sizes and bag weights, and consider store pickup or delivery to streamline your project.