Managing Salinity in Clownfish Fry Tank?

[SnowDog]

What's the best way to top off the fry tank to maintain the right salinity?

I've been dripping in RODI water, but not sure if that is causing issues with my rotifer population. I recently lost a small group of fry when I started the drip and a few hours after saw a ton of rotifers floating on the surface. My other guess is it might have been due to too many rotifers in the fry tank depleting the 02.

This is what it looked like with rotifers on the surface like a film. Thoughts?

 

[SEMA]

Could of been a couple things, temp, salinity swing to quick, oxygen saturation. But I also wouldn't rule out nutrient problems or something not related to adding freshwater. Could be coincidental.

This must be a very small system/tank Since your asking about top off. I would top off frequently as possible (daily), possibly drop an air stone in before dripping it, make sure temp is close and not to far off of tank temp. Whatever fry/food your raising is extremely sensitive to salinity changes, temp, nutrients, oxygen levels shouldn' change much if you have plenty of air agitating the surface as well as keeping food suspended and toping off with only a gallon or 2 very frequent.

Hope this helps, good luck

 

[SEMA]

I re-read the comment and see rotifers are going to surface. They will be attracted to light, and if not enough surface flow, they will die on the surface if left to long(use pvc air lifters). Put a light under tank or on bottom sides. Any dead food will directly relate to nutrients and micro bacteria that can take fry with it. Keep algae free, don' let buildup of poop or any organic matter, keep the tanks very sterile.

 

[SnowDog]

Here is my set-up. This was only my second attempt at raising the fry so I have a lot to learn. Any feedback would be really helpful.

- Broodstock are in my DT, laying eggs on a clay pot. I remove the pot prior to hatch and place in fry tank.
- Fry tank is a 10g tank, filled with about 5g water (SG 1.025) from the main tank to start.
- It has a heater (temp 81) and airstone.
- Ammonia alert badge
- The tank is covered on all sides with black construction paper and bottom is painted white.
- Feeding Rotifers and begin TDO A at 4 days. Rotifers grown in 5g white buckets with salinity at 1.022
- Tinting water and feeding rotifers with RGComplete. It is added to the fry tank via drip mixed with fresh SW.
- Lighting with a single 60W 5000K LED bulb about 24 inches from the top (Fry seem OK with this and do not hide on the bottom). End of the tank with heater and airstone is slightly shaded.

In terms of keeping the tank "sterile" I have been vacuuming it with a rigid airline after day 4, but there is still some residual "residue" on the sides of the tank. Ammonia has never been an issue so far.

Question: How "dark" should I be tinting the water? Right now I am tinting it pale green so I can just barely see the bottom of the tank.

Things I am going to change for the next batch.

• Increase starting water volume to 6G and raise to 9g over the first few days via water changes / dripping new water with RGComplete to tint.
• Increase rate of airflow to improve surface agitation and suspend food
• Monoitor rotifer saturation in fry tank and filter out if it gets too high
• Preheat

 

[WestOhooligan]

Just from looking at that pic, I'd say your density is way too high in the fry tank. Your setup seems pretty good. DO NOT use RG Complete to tint the water, it's too viscous and causes problems. I used to lose most of my fry when tinting with RGC. It is not meant for tinting the water. I actually do some work with Reed Mariculture, use one of the greenwater products to tint your fry tanks.

But as far as managing salinity, I would draw a level line on the glass, and aim to keep my water at the line by just using an airline to slowing top the tank off with RO/DI, so you're doing it right from what I can tell. I used to use the airline valves to control the rate of flow.

 

[SnowDog]

Thanks for the info. I've read posts from people that have success with RGC, and some that have not. I have some Nanno green water/culture starter that I can use. But then I'll need to use something for the ammonia. I have some Seachem Amguard and can use that I guess.

 

[Dsnakes]

I hope I have some fry to try and raise eventually. What type are your pair that is laying?

 

[WestOhooligan]

Thanks for the info. I've read posts from people that have success with RGC, and some that have not. I have some Nanno green water/culture starter that I can use. But then I'll need to use something for the ammonia. I have some Seachem Amguard and can use that I guess.

I too have heard of people using RGC for green water, but if you talk to someone at Reed, it is not meant for that and has been for sure attributed to fry mortality. I used Prime to detox ammonia, but I'm sure the Amguard will work too. I used to use those stick on ammonia badges to give me an idea.

 

[SnowDog]

I hope I have some fry to try and raise eventually. What type are your pair that is laying?

My pair is female Goldflake Maroon & male Lightning Maroon. They lay eggs every 10 days and the eggs hatch on the 8th night. Just had a bunch hatch last night and now I have a lot of new fry. This was my best hatch by far.

 

[WestOhooligan]

My pair is female Goldflake Maroon & male Lightning Maroon. They lay eggs every 10 days and the eggs hatch on the 8th night. Just had a bunch hatch last night and now I have a lot of new fry. This was my best hatch by far.

Nice, that was a pair I have been considering myself. I know getting gold lightning has been a goal of many breeders lately.