Stripe-face Calamiana

Where they come from

Stripe-face Calamiana (Eugnathogobius mindora) is one of those gobies that makes you realize "brackish" is not just a vague middle ground. In the wild they show up around coastal streams and estuaries in the Philippines, where the salinity can swing with tides and rain. That background explains a lot of their quirks in the aquarium: they like structure, they like food that moves, and they do best when you treat the tank like a little shoreline, not a community freshwater setup with a teaspoon of salt.

Setting up their tank

Think shallow shoreline with lots of hidey holes. Mine settled in way faster once I stopped trying to make the tank look like a planted freshwater scape and leaned into sand, rock, and hard cover. They spend a lot of time on or near the bottom, and they really appreciate having several "addresses" to pick from.

• Tank size: I would not start with less than 20 gallons, and bigger is calmer if you want more than one.
• Substrate: fine sand. They sift and scoot around, and rough gravel can beat up their underside.
• Hardscape: piles of rounded rock, chunks of coral rock, PVC elbows hidden behind rocks, and driftwood (if it is not leaching too much). Make lots of tight caves.
• Flow and filtration: moderate flow with high oxygen. A strong HOB or canister plus a powerhead works well. They hate stale water.
• Lighting: whatever suits you, but give them shaded areas. Bright, bare tanks keep them jumpy.
• Lid: tight. Gobies can teleport out of tanks through tiny gaps.

For salinity, I have had the best long-term results treating them like true low-end brackish fish, not "a pinch of salt" fish. Use marine salt mix, not freshwater aquarium salt. Mix new water in a bucket, heat it, aerate it, and match it before it hits the tank.

I keep them with a specific gravity in the neighborhood of 1.005-1.010 most of the time, depending on what else is in the system. They can handle a bit outside that, but they get cranky if you bounce it around. Temp in the mid to upper 70s F is a safe zone, and I keep the tank clean but not sterile. A little biofilm on rocks actually seems to help them feel at home.

What to feed them

These are not "flake gobies" in my experience, at least not at first. Most Stripe-face Calamiana I have seen come in skinny, and the ones that do well are the ones you get eating real meaty foods early on. They are visual feeders and love movement.

• Go-to foods: frozen mysis, frozen brine (as a treat, not a staple), chopped krill, chopped clam, and good quality frozen blends.
• Live foods that really help: live blackworms (if you can get clean ones), live brine shrimp, small ghost shrimp, and sometimes mosquito larvae (if you are 100% sure they are pesticide-free).
• Pellets: once settled, many will take small sinking carnivore pellets. I start by mixing pellets into a frozen feeding so they accidentally learn what they are.

Feed smaller amounts more often while they are settling in. A big dump of food just rots in brackish tanks if you do not have a cleanup crew that can handle it. Watch the belly line: slightly rounded after a meal is what you want. Sunken bellies are your early warning sign.

How they behave and who they get along with

They are bottom-oriented, a bit suspicious, and surprisingly bold once they claim a cave. The personality reminds me of a small predator that wants to be left alone until food shows up. They are not hyper-aggressive like some gobies, but they will defend a spot and they do not enjoy being crowded.

• Best tank style: species-focused or a carefully picked brackish community with lots of floor space and hiding places.
• Good tankmates: small to medium brackish fish that stay out of their face - think peaceful bumblebee gobies (in the right salinity), some mollies, and other non-bullying brackish species.
• Avoid: fin nippers, very fast food hogs, big scats/monos in smaller tanks, and anything that will sit on the bottom and compete for caves.
• Shrimp/snails: small shrimp can become snacks. Tougher snails sometimes work, but do not count on them as a cleanup crew if the goby decides they are food.

One thing that surprises people: they can look "shy" when they are actually stressed by activity. If they only come out at lights out, try adding more cover and reducing boisterous tankmates. Once mine felt secure, they were out in the open a lot more.

Breeding tips

Breeding them in home tanks is possible but not something I would call straightforward. Like a lot of brackish gobies, the big hurdle is not getting eggs, it is raising larvae. Adults may spawn in a cave and guard the site, but the babies often need different conditions and foods than most hobbyists have ready on day one.

• Give them caves with a single entrance. Small PVC sections tucked into rockwork work great.
• Condition with meaty foods and keep the water stable. Spawning attempts seem to line up with steady routines.
• If you see guarding behavior, do not constantly flashlight the cave. They can abandon if they feel harassed.
• Have larval food ready if you want to try raising them: rotifers, greenwater/phytoplankton, and then baby brine. Be ready for a project.

Common problems to watch for

Most issues I have seen with Stripe-face Calamiana come down to two things: they were kept freshwater for too long, or they were put in a brackish tank with sloppy salinity and dirty substrate. They are not forgiving of long-term "almost right" conditions.

• Not eating: common after import. Dim the lights, add more cover, and offer live or frozen foods right at their hide. Check that tankmates are not intimidating them.
• Skinny with pinched belly: treat as an urgent feeding and quarantine problem. Many wild fish carry internal parasites. If weight does not improve with heavy feeding, you may need to deworm in a hospital tank.
• Fin damage and scrapes: usually from rough decor, sharp rock, or being chased off the bottom. Swap to sand, smooth sharp edges, and add more caves.
• Ich-like spots: brackish can still get parasites. Treat in a separate tank if you can, and double-check salinity and temperature stability. Sudden changes tend to trigger outbreaks.
• Jumping: almost always a lid issue or a stress issue (too bright, too bare, too much chasing).

If you keep one takeaway in mind, make it this: these gobies reward consistency. Same salinity routine, same feeding rhythm, and a tank layout that makes them feel like they own a little chunk of shoreline. Do that, and an "advanced" fish starts acting a whole lot more reasonable.