Just thought I'd share my ray experiences of the last few months. This is a looong story but it may be helpful for other ray owners especially those concerned with mixing ray species or keeping retics successfully. It has been pretty interesting and a lot of unexpected things have happened but I'm hoping I have everything straightened out by now. It started about late january/early feb when I took home a P. sp "peru" (Yellow Hystrix). It is an immature male, about 6" and was placed in my 90gallon ray tank. Already in the tank were 2 smaller retics I had had since about April of last year, both of which were exceptionally healthy and eating almost anything I tossed in the tank. Both had grown significantly since I had them, although not nearly as quickly as a motoro. The yellow hystrix had been at an lfs for just over 4 months, and eating worms, feeders, ghost shrimp and occasionally clam.
The tank, although small, was more than sufficient for smaller rays and parameters remained consistently good. The highest nitrate reading I ever got was 60ppm and that was after skipping a water change. pH constant at 6.8. 0 No2/NH3/NH4. After adding the new ray, the two retics remained pretty dominant and got the lion's share of the food. The "yellow hystrix" was more active overall, and spent a good deal of time swimming through the tank's middle levels, where the retics were almost always on the bottom.
I noticed some injuries on the smaller retic about mid february, which I attributed to a small pleco. I took out the pleco, they healed (slowly) and scarred up. Then I noticed some small white spotting on its disc around the scars, which were I believe a secondary fungal infection. I treated with salt and bumped the temp to 86. The spots went away, but were back within a few days. This retic was spending much more time under the gravel than it had previously. I treated with pimafix in conjunction with the salt and high temp and they subsided, although it continued to bury itself more often. Then two weeks ago it completely broke out, stopped feeding, and within 24 hours had curled and died. The other rays were both healthy and eating well. Last week, my darker retic began burying itself, especially under driftwood. It became lethargic and became less active at feeding time. Not looking forward to another loss, I moved this retic into a 150 by himself. He did not transfer well, developed a slight curl and didnt move for nearly 6 hours. After a 25% w/c, some salt, and the addition of chemipure to the filter, he has returned to his original state of activity and health, actively hunting, eating, and exploring.
What I took from this experience is that retic rays, while relatively hardy if they arrive in decent shape, can not tolerate the presence of larger, more active rays like motoros or the like for long periods. While there may be no direct aggression, or even competition for food, the stress builds up and can overpower their ability to deal with "normal" stressors, like minor injuries. I would recommend those keeping retics to carefully choose their tankmates, and carefully monitor their activity levels long after such tankmates have been added. I'll try to get some pics up later of the surviving rays and their tank setups.
The tank, although small, was more than sufficient for smaller rays and parameters remained consistently good. The highest nitrate reading I ever got was 60ppm and that was after skipping a water change. pH constant at 6.8. 0 No2/NH3/NH4. After adding the new ray, the two retics remained pretty dominant and got the lion's share of the food. The "yellow hystrix" was more active overall, and spent a good deal of time swimming through the tank's middle levels, where the retics were almost always on the bottom.
I noticed some injuries on the smaller retic about mid february, which I attributed to a small pleco. I took out the pleco, they healed (slowly) and scarred up. Then I noticed some small white spotting on its disc around the scars, which were I believe a secondary fungal infection. I treated with salt and bumped the temp to 86. The spots went away, but were back within a few days. This retic was spending much more time under the gravel than it had previously. I treated with pimafix in conjunction with the salt and high temp and they subsided, although it continued to bury itself more often. Then two weeks ago it completely broke out, stopped feeding, and within 24 hours had curled and died. The other rays were both healthy and eating well. Last week, my darker retic began burying itself, especially under driftwood. It became lethargic and became less active at feeding time. Not looking forward to another loss, I moved this retic into a 150 by himself. He did not transfer well, developed a slight curl and didnt move for nearly 6 hours. After a 25% w/c, some salt, and the addition of chemipure to the filter, he has returned to his original state of activity and health, actively hunting, eating, and exploring.
What I took from this experience is that retic rays, while relatively hardy if they arrive in decent shape, can not tolerate the presence of larger, more active rays like motoros or the like for long periods. While there may be no direct aggression, or even competition for food, the stress builds up and can overpower their ability to deal with "normal" stressors, like minor injuries. I would recommend those keeping retics to carefully choose their tankmates, and carefully monitor their activity levels long after such tankmates have been added. I'll try to get some pics up later of the surviving rays and their tank setups.
