Motoro stingray    5/15/09
Hi. I sent a question a few months back asking about breeding Motoro stingrays ( spelled breeding, Breading )
<Mmm... breaded stingray!>
I now have a concern about something else. I had both stingrays a male approx 9" and a female approx 10" in a small 90 Gallon tank. (27" wide X 52" long and 18" deep approx) My problem was other than the size Too small.
The Male became to aggressive and chewed off the lower disk and fins of the female. I moved the Male into there to be new home a 250 gal tank 36" wide X 72" long and 30" deep. This tank has been cycled for 4 months and has two Fluval FX5 filters and one Aquaclear 500 filtering it. It has two Eheim 250W heater.
<Sounds good; do keep the heater protected with a "heater guard" though, or better yet, inside the sump. Stingrays easily burn themselves on glass heaters.>
With glass bead substrate. Very soft and non abrasive ( like tiny marbles)
<Never heard of this; can't say I like the sound of it all that much, so do check with other Stingray keepers that it is known to be safe. Even if it is smooth, the texture or colour may be off-putting. If all else fails, plain vanilla gravel works, as does smooth silica "silver" sand from garden centres. Neither of these costs much. Do observe all the usual rules when selecting, using substrates re: being lime-free, non-abrasive, thoroughly cleaned before use, and regularly cleaned once installed.>
With a large pc of bog wood for decor. I do a 30% -35% water change every 4-5 days. Last time I checked 2 days ago the ammonia, Nitrates and Nitrites where at 0ppm The PH Is 5.5 The temperature was 81 f But I
replaced a defective heater and it is now 76 f. The only fish in the tank are 2 angelfish, 3 SAE's and 20 Guppies.
<Fine.>
The male Stingray has been in the tank for 30 days. He spends most of his time swimming against the glass near the surface of the water in the same spot. When I first put him in the tank he ate like a pig as usual. Silver sides, night crawlers, black worms, Ghost shrimp and sometimes grubs or crickets. But now he is eating very little and not so eager to eat. Just swimming in his spot or sitting on the bottom. Do you think he just needs more time acclimating to his new tank? or should I be more concerned about something else?
<With Stingrays, you should *always* be concerned when these fish don't behave normally. Put simply, behaviour is your first and only warning of problems; by the time symptoms of ill health appear, it's often too difficult (or impossible) to treat them. So yes, review water chemistry, water quality in particular, but also potential social issues such as the Siamese Algae Eaters "nibbling" on the Stingray and annoying it. Don't keep adding food while he isn't eating, but do try offering earthworms after 3-4 days of starving to see if he's ready to eat again. Do consider possible sources of toxins: paint fumes, cleaning agents, etc. Check water circulation throughout the tank is adequate: is the bottom layer of water being moved about? Or just the top? Does adding extra aeration make a
difference? Rays are super-sensitive to low oxygen concentration, which can be caused by poor circulation and excessive heat. Look for signs of decay in the tank: particularly organic debris stuck in the substrate. Perform a
large water change, controlling pH and hardness changes as much as possible.>
When he was in the small tank with the female he was doing better under poor tank conditions. Where the female is now flourishing and healing nicely. Getting bigger and fatter. Any suggestions would be helpful.
Thank you. Kevin
<These are difficult fish at the best of times. If water quality/chemistry are good, I'd be reviewing tankmates, diet, substrate, and sources of disturbance such as loud TV sets close to the aquarium. Cheers, Neale.>