I have about 45 Gonis and 4 Alveopora in a 90 gallon AIO style tank. No filter socks, reactors or skimmers. I’m using extra rock in back for in “in tank” refugium. That’s the only extra I have. I do use a Fluval 407 canister for chemical and polishing of the water. Minimal water changes. Par 120ish to mid 200s. Moderately strong pulse flow. For dosing I use B-Ionic 2 par, B-Ionic Magnesium(small doses daily), kz 4 part micro element weekly, Reef Plus for Aminos and some vitamins every 3d days or so. I also add phyto from Dinkins daily. I broadcast feed a mix of frozen daily and a mix of powdered foods every week. Here’s my tank-
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Goni's (according to Justin Credible) seem live better in Goni crowds. That's not to say you can't keep a loaner. I also add my own DIY brew of Fe, Mo, Mn, I and yes Sr. All bought on
Amazon and I use an analytical balance to weigh out for my solutions. I have a skimmer and intermittently use Rox0.8 carbon. I have a deep sand bed and 4 larger fish (Foxface, Tangs) in a 135 Gallon. Fish poop is great Goni food. Do you have enough large fish. I have a hydraulically connected bare bottom frag tank and frags of my DT Goni's grow just as well in the bare bottom.
I feed 1-2 times per day flake food (Prime Reef Flakes), Reef-Roids and fresh sea food counter prep I make myself. Fresh sea food is gulf shrimp, crab, salmon and anything else they want to throw away. I think the bacteria from this stuff is beneficial for Goni's. I have a 20 gallon aquarium beneath the DT that has about 18 gallons of water and the top 1/3 is filled with chaeto and tons of zooplankton, pods, worms, etc. Those keep my mandarin fat and may be feeding the goni's.
I have 4 Hygger 24V wave makers in the tank for circulation and they really move the water a lot. The Goni's don't care. Those are in addition to a Iwaki RLT-30 return pump from the 2 x 20 gal sump tanks.
Lighting is 2 x Kessil AP9x with some T-5 supplement.
My goni's generally are not upset by water changes or they seem to look fuller for a few days afterwards -- - especially if I stir up the sand in the W/C process.
I've raised Goni's successfully in 75-250 PAR - - but you can't just willy-nilly move them around. They need to acclimate over 2-6 weeks each time they move. If I have a Goni going "South" I cut it up on the band saw and dip it in H2O2 (10mL of 3% solution into 90mL of tank water for 10 min). If your Goni gets hair algae use that H2O2 solutions 1 time per week until the GHA is gone. Did this with an ORA red and it reclaimed real-estate previously stolen by GHA. It seems fragged Goni's do better than the parent (mostly). Maybe that is a Darwinian thing.
Stability is very important for Goni's (and other stony's). I've been guilty of letting my PO4 levels get too low (hence the daily reef roids). My NO3 is about 30-50 ppm (Nyos kit) and my PO4 is 0.030-0.060 ppm (Hanna ULR Phosphorus). Most of my Goni's sit on the sand.
Goni's do weird things: they pull in for days, then bounce back in one day like nothing happened. They also pull-in and "balloon" each polyp, then bounce back. Sometimes this behavior is their character, sometimes this is stress. Stress is when it takes 2-4 weeks for them to bounce back.
It's hard to tell what might be too much or missing from the OPs system, but I'm glad I found this thread with so many sharing their system parameters.