I wanted to make a post calling attention to my favourite aquarium sleeper product: Safe-T-Sorb all purpose absorbent. STS is a calcined montmorillionite clay product, sold as a spill absorber for oils, paints, etc. It is essentially clay kitty litter, but fired hotter creating harder granules. And IMO it is maybe the best substrate going.
Pros:
- STS has a natural blend of irregular particle sizes, shapes and colours which provides a very natural effect. Looks good mixed with pea gravel, but is finer and doesn't trap mulm as badly. But it's coarser than sand and won't compact.
- STS has extremely high Cation Exchange Capacity (CEC). This means that it is really effective at binding ions from the water to the surface of each granule. Why is this valuable? STS will naturally pull fertilizers out of the water column, and hold them in the substrate for plant roots.
- Doesn't get "exhausted" like aquasoil, and eliminates the need for root tabs.
- Montmorillonite is used as an immune booster and mineral source in fish food: https://www.northfin.com/product-info/
- It's also used as a flocculant water clarifier in koi ponds: https://summitchemical.com/products/clear-water-pond-clay/
- Because of it's ability to absorb and hold liquid, it is excellent for dry starts.
- It's extremely affordable. Carried in many hardware stores and tractor supply stores. You can get 40lbs for about $20.
Cons:
- It's very dusty out of the bag. It's best to give it a thorough rinse (or even screen it), but it will never rinse clean, and it will kick up dust when disturbed. BUT, because of it's benefits, kicking up dust is essentially doing a water treatment and giving your fish a multivitamin, so I'm not sure I really consider it that much of a drawback.
- It is very light, which can make planting difficult. But plants root quickly and securely.
Risks:
- Because of that high CEC, it will pull everything it can out of the water, including all available carbonates. It will cause a PH crash initially if you let it. STS should always be "charged" before using. This means providing a bunch of cations for it to bind until all it's capacity has been used up. You can do this cheaply with KH booster and epsom salts, or do it with your own blend of fertilizers. Once charged, STS will only pull molecules from the water to replace the ones consumed by plants.
TL;DR STS is cheap, and every tank I've used it in has had crystal water, well conditioned fish, and thriving plants with bananas root structures. Definitely worth the extra setup effort. Highly recommended.
Posted by justmyfishaccount