Tankmates for Yellowhead Jawfish

[Teeter]

For the last couple years, I had an "empty" (still running, ATO used, just no light or feeding, with a few hermits and snails living off the algae and pods) Innovative Marine 15G Cube and finally wanted to do something with it. I decided to go with a Yellowhead Jawfish (Opistognathus aurifrons) macroalgae-heavy tank. It's been running for a couple months now, with a handful of macroalgae being added around two weeks ago. The current stocking is:

- Pair of Yellowhead Jawfish
- A few photosynthetic gorgonians (Pterogorgia and Plexaura, I believe)
- ~10 Blue Leg Hermits
- ~10 Nassarius vibex
- A few Nerite snails
- 3 Pom Pom Crabs
- Handful of red and green macroalgaes (no caulerpa, but maybe in the future)

Over the last couple weeks, I've tested NO3 and PO4 daily/every other day, and most of the time the results are the same: low or no PO4, and no NO3. Because of this, I've been dosing ChaetoGro daily, but am reading the same results. My question is what is the best way to go about keeping these numbers higher in a tank where it will likely be consumed quickly?

I've considered adding another fish, likely a small goby, so something from the Elacatinus genus, but I'm open to other ideas. The only concern I have is the potential for a negative reaction from the jawfish. They have been surprisingly outgoing, with them almost always being totally out of their burrow and often swimming up to the glass whenever they see me nearby. The tank is in my bedroom, so they have become very accustomed to me being present, which I'm sure has helped overcome any natural shyness they might normally display. I'm concerned a tankmate might bring this shyness back out, but a goby doing so seems unlikely.

I've been absolutely loving the tank and the jawfish, and will probably make a build thread at some point. If anyone has any input on the fish behavior, nutrient upkeep, or anything else, I'd love to hear it. Thanks!

 

[jonsreef2reef]

The thing that jumps out: ChaetoGro is nitrate- and phosphate-free -- it's iron and trace elements to fuel macro growth, not an actual N/P source. So you've been feeding the algae while leaving the real nitrogen and phosphate input at whatever your bioload puts out, which in a tank this lightly stocked is close to nothing. The macro and gorgs are just pulling it to zero as fast as it appears.

If you want the test kit to actually read something, I'd dose nitrate and phosphate directly -- Brightwell NeoNitro + NeoPhos, or a DIY equivalent, kept somewhere around 100:1 NO3:PO4 by ppm. Feeding more works too, but it's slower and harder to control when your export is this aggressive. Honestly I'd also just make peace with it reading low while the macro grows in, and dose toward a small target rather than chasing the number day to day.

On the goby -- an Elacatinus should be a non-issue. They sit in completely different water than a jawfish and neon gobies are about as peaceful as it gets, so I'd be surprised if it brought the shyness back out. The bit of extra bioload even helps your nutrient situation a touch, though a fish that small won't move the needle much. Sounds like a great little tank â would read the build thread.

 

[Teeter]

The thing that jumps out: ChaetoGro is nitrate- and phosphate-free -- it's iron and trace elements to fuel macro growth, not an actual N/P source. So you've been feeding the algae while leaving the real nitrogen and phosphate input at whatever your bioload puts out, which in a tank this lightly stocked is close to nothing. The macro and gorgs are just pulling it to zero as fast as it appears.

If you want the test kit to actually read something, I'd dose nitrate and phosphate directly -- Brightwell NeoNitro + NeoPhos, or a DIY equivalent, kept somewhere around 100:1 NO3:PO4 by ppm. Feeding more works too, but it's slower and harder to control when your export is this aggressive. Honestly I'd also just make peace with it reading low while the macro grows in, and dose toward a small target rather than chasing the number day to day.

On the goby -- an Elacatinus should be a non-issue. They sit in completely different water than a jawfish and neon gobies are about as peaceful as it gets, so I'd be surprised if it brought the shyness back out. The bit of extra bioload even helps your nutrient situation a touch, though a fish that small won't move the needle much. Sounds like a great little tank â would read the build thread.

You know, I thought I was pretty decent at not dosing unless I understood why I was dosing and what exactly that supplement consisted of, but it never occurred to me that ChaetoGro wouldn't have the necessary components I was looking for. Thanks for pointing that out, and lesson learned! I have NeoPhos and NeoNitro on hand already, so I'll begin dosing those instead.

Fair point on the goby, but with the tiny bioload not helping much in nutrient production, would you recommend anything else fish-wise? I was also considering multiple small gobies, like Elacatinus and a T. multifasciatus, or a pair of either. If dosing is really the most efficient way to keep those levels steady while also maintaining a good environment for the jawfish, I'm 100% fine with that.

 

[Firefish89]

I had a firefish in a 30 gallon with a pair of jawfish and that seemed to work.

 

[jonsreef2reef]

You know, I thought I was pretty decent at not dosing unless I understood why I was dosing and what exactly that supplement consisted of, but it never occurred to me that ChaetoGro wouldn't have the necessary components I was looking for. Thanks for pointing that out, and lesson learned! I have NeoPhos and NeoNitro on hand already, so I'll begin dosing those instead.

Fair point on the goby, but with the tiny bioload not helping much in nutrient production, would you recommend anything else fish-wise? I was also considering multiple small gobies, like Elacatinus and a T. multifasciatus, or a pair of either. If dosing is really the most efficient way to keep those levels steady while also maintaining a good environment for the jawfish, I'm 100% fine with that.

Sorry for the late reply, just saw this. Since you're dosing N/P now, I'd stop treating stocking as a nutrient lever and just pick fish you want to watch — one small fish won't move your numbers anymore.

The jawfish-specific thing: they defend their burrow, so I'd skip a second sand/burrow dweller (shrimp goby, dartfish) in a smaller footprint. Elacatinus and greenbanded both sit in the rockwork rather than the open sand, so they stay out of the jawfish's zone — clean picks. One heads-up: greenbanded group-keeping is genuinely split, some run trios introduced at once, others find they squabble in a small tank and do best as a pair. I'd lean pair unless you've got the footprint.