MultiHub Forum

I'm attempting to create a small, self-contained biotope aquarium for a specific species of endangered local freshwater shrimp, housed in a repurposed 20-gallon glass tank on my apartment's north-facing windowsill. My budget is tight, around $180, and I need to replicate a shaded, slow-moving stream environment with precise water parameters—cool temperature, very low hardness, and a specific pH—using only passive cooling and natural filtration from live plants and leaf litter, as I cannot fit any bulky equipment. The challenge is achieving and maintaining stable, cold water through the summer without a chiller, and I'm unsure how to design the hardscape with collected stones and driftwood to provide adequate hiding spots and biofilm surfaces while ensuring nothing leaches minerals and alters the delicate water chemistry. I need to have the system fully cyclated and stable within the next five weeks before introducing the shrimp.

Go inert with the hardscape: rinse stones, boil driftwood for weeks, then stack for hiding surfaces. Use RO water (GH 0–2, KH 0–2) and target pH around 6.5–7.0; add a tiny buffering only if needed. Plant dense, shade-tolerant greenery and leaf litter to fuel biofilm. For cooling, keep the tank out of direct sun, drape a blackout cloth, and use a small fan to induce evaporation; top off with RO water as you cycle over five weeks.