Trouble in paradise

[BedScien]

I thought I had my three figure 8s sorted and had a manageable routine going with the water changes but now...

One of my figure 8s is chasing the other two around the tank. Anyone had this experience? What happened? Did it lead to serious aggression?

[Pufferpunk]

Tank size? FTS?

[BedScien]

100L maybe a bit more. i dont know what fts means.

[Pufferpunk]

Full tank shot, so I can see how it's decorated.
100 liters - 26 gallons. Rule of thumb for F8s is 15g for 1 & 10g for every extra.
library/puffers-in-focus/fig8/

[BedScien]

theres lots of fake plants and i move them around when i do a water change.

[Pufferpunk]

Not enough room for territories.

[RTR]

+1 to Pufferpunk's comments. IMHO, it is not nearly enough room. Even with the water volume suggested, there is never any guarantee that any group of puffers will remain compatible. Actually there is no tank volume of standard tank size that can guarantee compatibility IME.

[BedScien]

I prepared another smaller tank for the aggressive puffer. Me mucking around doing this scared them which seemed to temporarily solve the problem for that time at least so I've left them in the same tank for now. I've put the cave-like decorations back in the tank as i figured that would break up the sight more and give them more sheltered places to sleep separately. I'm not sure if that helped or not but the aggression has stopped. They are very tolerant of each other now with their usual slight caution.

Do figure eights always pace up and down the sides of the tank? Have you seen this behavior in singleton f8s? I'm wondering if the pacing and territoriality might be linked. Could, of course, just be that fish are generally dopey and habitual creatures though...

[RTR]

Pacing is a form of exercise, usually (as with big cats in zoos). It usually indicates too small a tank and/or insufficient current or both.

F-8s do need/prefer tanks with a larger footprint over tanks with deeper water column, In other word, they will do better for me in 33XL tanks than in 30EH tanks. The former is 4 feet wide, while the later is 2 feet wide. The former has more than 2x the footprint of the latter, even though the wider tank may and for me usually does hold less water due to having more substrate. For me, F-8s love those long/wide tanks. If you are trying co-housing F-8s, larger footrprint tanks are very important. I would use a 40-long tank at least if I were trying 3 together, but would likely do better with a 75.

HTH

[BedScien]

Nice one, RTR. Concise and educational as usual
Will look at a few options within my price range.
Maybe I'll set one or two more currents up as they seem to enjoy swimming into it.

[RTR]

Fine-tuning the current/currents in a tank is pretty time-consuming for me, but I do consider it worth the effort. Once set, my tanks tend to fairly stable for years with only some fine-tuning for plant growth and pruning in FW planted tanks.

[BedScien]

That's my aim for this brackish tank - To overtime develop a system that is as far as possible self-sustaining.

Going back to the aragonite sand you suggested a while ago, I may use some as a substrate in a the moss refugium i'm hoping to build. With less frequent water changes hopefully becoming an option, I would want to replace the effect of the tapwater limescale.

[bertie 83]

You will be doing more than 50% water changes weekly to keep a tank that size with 3 f8s in stable. But much likely 2x 50% weekly as they grow. A bigger tank is needed to stop aggro

[BedScien]

My tank seems to be okay with 30% changes at the moment but I will keep an eye on it! thanks!

[RTR]

I had enough issues at 50% weekly partials for F-8s. I would not count on keeping the organics down with less. Upgrade the tank to a larger footprint before adding another tank, or expect to have to break the fish up to separate tanks. Bumblebee gobies can help clear the scraps fron F-8 feeding, but you don't have space - they are more likely to be eaten themselves.

HTH