Rhinogobius Duospilus In Trouble?

[galerian_ash]

This morning, I got what I believe are 1 male and 3 female Rhinogobius duospilus. 1 is definitely a male and is a bit larger, he had the most dominant colors in the store tank. I acclimated them to my 40g breeder community and lowered the temp to 75F.

I know this is still a bit high for them, so I filled up a 20g long to the same temp as the 40g and set the heater to 68F. I netted two of the females over and they seem to be doing ok so far. Should I net the rest over, including the male who is stuck to a back side corner of the tank and breathing heavily? Is he stressed from the hi temp?

The 20g is uncycled but I put in the sponge pre-filter from the 40g, which has been in there for 2.5 weeks, so should have some good bacteria.

 

[nmonks]

Do think about their habitat. These fish live in very shallow streams where the water along the bottom is cool, well-oxygenated, and flowing quickly. That's what you need to provide for long-term success. Ensure the filter provides high turnover rate (8, ideally 10 times the volume of the tank in turnover/hour). Keep the water cool; 18 C/64 F is ideal. Add a block of ice if needs be. Do a "cold" water change (say, 50%, with water from the cold tap, but not much colder than 10 C/50 F) and see what happens. If the male goby perks up, then temperature and/or oxygen concentration could well be the issues. Check ammonia and nitrite level (both need to be 0). Water chemistry isn't a big deal, but avoid extremes. Salt isn't required, but feel free to use brackish water around SG 1.005 if you're worried about velvet or whitespot (velvet especially causes fish to breathe heavily because it attacks the gills first).

Cheers, Neale

I know this is still a bit high for them, so I filled up a 20g long to the same temp as the 40g and set the heater to 68F. I netted two of the females over and they seem to be doing ok so far. Should I net the rest over, including the male who is stuck to a back side corner of the tank and breathing heavily? Is he stressed from the hi temp?

 

[galerian_ash]

Thanks for the informative post. I just turned the heater to 65F (the lowest setting) and added aquarium salt at 1 tbsp per 5 gallons. The male is still breathing hard and has stressed coloration.

I'm thinking of dosing the entire tank with Mardel Coppersafe tomorrow. Would you recommend that? The male hasn't eaten in 10 days, so I'm worried he won't make it.

 

[galerian_ash]

The male goby is dead, presumably from the aquarium salt I added in addition to whatever he might've had already. I did a 50% water change, but he was already upside down before the tank filled up. He darkened to a deep gray as his gill movement slowed to a stop. Any ideas what it might've been? Velvet, gill flukes, internal protozoans? I have 3 more female gobies.