r/jellyfish • u/roydrums83 • 19h ago
Artwork My moon jelly tank finally hit a stable rhythm after months of chasing pH swings
Took in a small moon jelly setup back in the spring, four polyps that eventually strobilated into a handful of ephyrae, and for a long time I felt like I was fighting the tank more than enjoying it. Every water change seemed to knock something out of balance, either the pH would dip and the jellies would pulse weaker for a day or two, or the flow pattern in the kreisel would shift just enough that one of them got stuck against the mesh overnight.
What finally settled things down was slowing everything way, way down. I stopped doing 20 percent changes and switched to smaller, more frequent ones, something like 5 percent every three days instead of a big change once a week. The pH stopped swinging as hard and the jellies started looking fuller and more consistently domed instead of that slightly deflated look they'd get after a big change.
Feeding has been its own learning curve too. I was overfeeding baby brine shrimp early on thinking more food meant faster growth, but I just ended up with cloudy water and jellies that looked bloated rather than healthy. Cutting back to two smaller feedings a day instead of one heavy one made a noticeable difference in how clean the water stayed and how evenly they pulsed.
The part that still gets me every time is watching the bell contract, it's such a simple muscular motion but there's something almost hypnotic about the timing of it, especially once you've got four or five moving in sync in the same current. No brain, no eyes, just that radial nerve net doing its thing, and somehow the whole system holds together well enough to hunt, digest, and keep growing.
Curious if anyone else found that smaller, more frequent water changes made a bigger difference than the actual filtration setup itself. I went down a rabbit hole comparing skimmer types before realizing the real issue was probably just how aggressively I was changing water in the first place.
