Better way to do water change with fry?

[Whaledriver]

I was wondering if there was a way to do a water change in the first 2-3 weeks of clown fish grow out.
Is there a way to use a membrane and a perilistic pump? This way you would just take the water and not the food the fry eat. Even the greenwater could be easy to replace if taken.
What about an airstone with a pump on the other end sucking water.

Just wondering since water quality is a big factor in the first weeks.

 

[Trademark]

I would recommend a flow through system

 

[billsreef]

I typically siphon out enough water for a water change with the daily bottom cleaning. IMO a pump and membrane set up would likely foul frequently and be more of a pain in the rear with maintenance than would be worth it. Especially since you'll still need to be siphoning the bottom of debris anyway

 

[Whaledriver]

I didnt think of the debris. I was just thinking of a continuous water change method that keeps water quality up. You could do a 100% daily water change with water from the main tank.

Is this worth it or just a pain? Would the improved water quality make a difference in size, survival or quality?

Maybe a syphon break type top off for input and a simple air stone syphoned into a bucket for taking water out.

 

[billsreef]

The problem with any sort of continous flow method is the screening. Any screen mesh small enough to keep both food and larvae in the tank is going to rapidly clog from both debris and the food itself. That will in turn lead to other problems like overflows. It can be done, but with lots and lots of daily (possibly several times daily) screen cleaning. While they are on rots, you would need a 40 micron screen, and for nauplii a 300 micron screen. You'd still loose some of the smaller rots and nauplii, so along with screen clogging you'd have to work a bit harder at maintaining food density.

 

[Whaledriver]

Keep it simple makes sense.

 

[cabrego]

Has anyone ever experimented with a sponge filter during the first week of larva raising?

 

[phil519]

Has anyone ever experimented with a sponge filter during the first week of larva raising?

the rotifers would all get sucked into it.

 

[cabrego]

the rotifers would all get sucked into it.

yes rots would get sucked into it, but I don't think they would die, and I also doubt they would get stuck in the filtration as the pore size is far to large.

Does any one know of a good reason not to use a sponge filter? It can be a hazard I know that since almost everything is a hazard for fry.

??

 

[Whaledriver]

I have read that rotifers are ok with sponge filters. They will get sucked in but they don't get killed. They can live in the sponge and eventually get sucked out with the bubbles.

At what point should you add the sponge filter? With green water and rotifer/copepods you don't need a sponge til after metamorphosis, right?. So at 7-10 days they can be moved to a larger container with a sponge filter. At this point you can move beyond rotifers to larger copepods, right? You can also start trying dry or frozen food.

 

[billsreef]

At what point should you add the sponge filter? With green water and rotifer/copepods you don't need a sponge til after metamorphosis, right?.

Right. It's also a good reason to use live phyto in your rearing tanks While a low flow sponge filter won't filter out too many rots, larvae can get trapped by the sponge filter as they are not good swimmers. Once they switch over to brine shrimp nauplii, they will be strong enough swimmers. However, the nauplii will sucked into the filter which will give the double whammy of dropping food levels and causing more decay from the nauplii getting trapped by the filter and dieing. I wouldn't start running a sponge filter till post metamorphosis when they have switched to mostly prepared foods.