How much light can a mantis shrimp handle?

[WilliamH2529]

Hey guys, so I have a coastal reef macroalgae tank which I quite enjoy but I’ve wanted to house a mantis shrimp in it, one of the smaller smasher species such as a lime green, purple spot, or tiger mantis. But I’ve heard they do not do well with light as it can cause shell rot I have plenty of sand and rock in the aquarium for it to hide away when necessary but I want to reduce light as much as I can while still growing the macroalgae, on the tank I have an ASTA20 16watt LED for salt water it can be adjusted just not very finely it has a 20%, 40%, 60%, 80% and 100% my question is what would be a happy middle ground where the mantis shrimp can handle the light and the macroalgae can still keep growing?

 

[blaxsun]

I think this is going to be very much trial and error. I would probably try 40% and go from there.

 

[Bucs20fan]

I agree, to go up from 40% but almost all of the coastal species can be found in just an inch or two of water. They get blasted by the sun at low tide while searching for food, this would prove to be something to your benefit.

 

[Steve and his Animals]

From what I've read, shell rot doesn't always seem directly linked to bright lighting in a lot of cases. A lot of mantises come in with it (from the ocean). I would say just do whatever you want with lighting and make sure he/she can build a hide that is 100% blacked out (even using black pvc pipe if you wish) and has proper conditions to molt quickly/easily so they can fight it before if becomes fatal.

 

[WilliamH2529]

From what I've read, shell rot doesn't always seem directly linked to bright lighting in a lot of cases. A lot of mantises come in with it (from the ocean). I would say just do whatever you want with lighting and make sure he/she can build a hide that is 100% blacked out (even using black pvc pipe if you wish) and has proper conditions to molt quickly/easily so they can fight it before if becomes fatal.

What would proper conditions for molting be? I try to keep my tank at 1.025 salinity, 77 is what my tank seems adamant at staying at lol, and I try to just keep nitrates and ammonia down but I’m not super worried about those with the macroalgae sucking it up.

 

[Eagle_Steve]

When I kept mantis in my macro tanks, I never had issues with the lights and the shrimp. They would just avoid the light most of the day and chill in their holes until a dove snail walked by lol. Then bam, grab it, and back to the hole. I would feed at early morning and at night though. It was also cool that the shrimps would wander around when the lights ramped down. On the tank where the lights did not ramp down, I just put some cheap white led strip pieces on the fixture and had them on a timer. They would come on about an hour before lights out and then stay on about an hour after. Did the same thing for morning also. Hour before lights on and then hour after lights on. This gave a "moonlight" affect and the shrimps were super active during this time.

The one main thing I learned was iodine needed to be dosed. Macros use it up, but shrimps need it to aid in molting. I used the Salifert test kit and while not 100% accurate, it was close enough to ICP tests that I could use it to make sure that iodine never dropped too low.

 

[Steve and his Animals]

What would proper conditions for molting be? I try to keep my tank at 1.025 salinity, 77 is what my tank seems adamant at staying at lol, and I try to just keep nitrates and ammonia down but I’m not super worried about those with the macroalgae sucking it up.

Properly clean water with the right levels of trace elements like Calc, Alk, and Iodine although knowing which species of iodine is useful is more of a challenge than anything.

Also, some people have found shell rot seems to be a bacterial infection of some sort, so running a UV sterilizer might help prevent it.

 

[Bucs20fan]

As long as you do a water change weekly/ biweekly you wont have to worry about iodine, But it is very important to have iodine in the water. If you dont have enough iodine it will cause a failed molt which is almost 100% fatal. But the good news is all salt mixes have enough required iodine to solve this issue.

 

[Duncan62]

Hey guys, so I have a coastal reef macroalgae tank which I quite enjoy but I’ve wanted to house a mantis shrimp in it, one of the smaller smasher species such as a lime green, purple spot, or tiger mantis. But I’ve heard they do not do well with light as it can cause shell rot I have plenty of sand and rock in the aquarium for it to hide away when necessary but I want to reduce light as much as I can while still growing the macroalgae, on the tank I have an ASTA20 16watt LED for salt water it can be adjusted just not very finely it has a 20%, 40%, 60%, 80% and 100% my question is what would be a happy middle ground where the mantis shrimp can handle the light and the macroalgae can still keep growing?

I have mantis in an acro tank. They don't get much light under a rock. That's where they will stay most of the time. Light you plants the way you need to. The mantis will be fine if he has rocks and sand.

 

[WilliamH2529]

When I kept mantis in my macro tanks, I never had issues with the lights and the shrimp. They would just avoid the light most of the day and chill in their holes until a dove snail walked by lol. Then bam, grab it, and back to the hole. I would feed at early morning and at night though. It was also cool that the shrimps would wander around when the lights ramped down. On the tank where the lights did not ramp down, I just put some cheap white led strip pieces on the fixture and had them on a timer. They would come on about an hour before lights out and then stay on about an hour after. Did the same thing for morning also. Hour before lights on and then hour after lights on. This gave a "moonlight" affect and the shrimps were super active during this time.

The one main thing I learned was iodine needed to be dosed. Macros use it up, but shrimps need it to aid in molting. I used the Salifert test kit and while not 100% accurate, it was close enough to ICP tests that I could use it to make sure that iodine never dropped too low

do you have an idea of how much iodine I want in the tank?

Properly clean water with the right levels of trace elements like Calc, Alk, and Iodine although knowing which species of iodine is useful is more of a challenge than anything.

Also, some people have found shell rot seems to be a bacterial infection of some sort, so running a UV sterilizer might help prevent it.

And do you have any recommendations for smaller UV sterilizers I could run? as well what process I’d want to run one? Ive never really used one for an aquarium.

 

[Tamberav]

Hey guys, so I have a coastal reef macroalgae tank which I quite enjoy but I’ve wanted to house a mantis shrimp in it, one of the smaller smasher species such as a lime green, purple spot, or tiger mantis. But I’ve heard they do not do well with light as it can cause shell rot I have plenty of sand and rock in the aquarium for it to hide away when necessary but I want to reduce light as much as I can while still growing the macroalgae, on the tank I have an ASTA20 16watt LED for salt water it can be adjusted just not very finely it has a 20%, 40%, 60%, 80% and 100% my question is what would be a happy middle ground where the mantis shrimp can handle the light and the macroalgae can still keep growing?

most smaller species should be fine with light and even a peacock is fine with high light as long as they have a fully dark burrow and clean water.

 

[WilliamH2529]

I’ll also ask if anyone knows I’ve heard when you first get them in they’re especially fragile, would it be smart to kill the lights for a few days while it settles in? Ive read about “stress molts” and how they can be especially dangerous.

 

[Eagle_Steve]

do you have an idea of how much iodine I want in the tank?

And do you have any recommendations for smaller UV sterilizers I could run? as well what process I’d want to run one? Ive never really used one for an aquarium.

I tried to stay around .06 for iodate and around .03 for iodine. On a Salifert kit, that is just a tint of blue in the vial for iodate and a tint of yellow in the vial for iodine. But in reality, as long as you keep it above 0 and below .1, you should be good for both.

Again, the salifert kits are not 100%, so there is room for error, which is why I kept them at those levels. It allowed for the margin of error both ways.

As others have said, if you are doing regular water changes, you may not need to dose. Especially if a small tank. But good to test a few times to check and see, especially since you are growing macro.

 

[WilliamH2529]

I tried to stay around .06 for iodate and around .03 for iodine. On a Salifert kit, that is just a tint of blue in the vial for iodate and a tint of yellow in the vial for iodine. But in reality, as long as you keep it above 0 and below .1, you should be good for both.

Again, the salifert kits are not 100%, so there is room for error, which is why I kept them at those levels. It allowed for the margin of error both ways.

As others have said, if you are doing regular water changes, you may not need to dose. Especially if a small tank. But good to test a few times to check and see, especially since you are growing macro.

I was considering the Hanna iodine checker

 

[Eagle_Steve]

I was considering the Hanna iodine checker

Never used it and I do not think it is really for marine tanks. It has a margin of error of .1 and appears to test for combined iodine/iodate. I believe Salifert (have no idea where my directions are lol, as I have the test procedure memorized) is .01 or .02 for margin of error.

.1 margin of error is quite a lot if you are trying to keep things at natural seawater levels of .03 for iodate and .06 for iodine.

 

[Steve and his Animals]

do you have an idea of how much iodine I want in the tank?

And do you have any recommendations for smaller UV sterilizers I could run? as well what process I’d want to run one? Ive never really used one for an aquarium.

I've always liked the Turbo Twist UVs, they make a pretty small one that I believe is 9 watts. Downside is it's kinda clunky and need an external pump since it runs outside the tank, so it really looks bad unless it's on a sump.