Question
QUESTION: I have a beautiful butterfly koi growing well & very happy in its aqaurium yeah its very young lil about 6" but I noticed one of his eyes is solid black with a silver dot center the other complete oppisite solid silver black dot pupil??? is that something I shuold be oncerend about? next at times they drift down to the bottom & just lingers motionless? not sure if theye taking a rest or sleeping doesnt do it for long periods just once or twice a day or after its done lookin for food

ANSWER: Koi may have differently colored eyes.  I've had goldfish with red around their eyes (not in the eye itself).  Koi can have black eyes.  I wouldn't worry about the eyes but if you send a photo of the two eyes, I can tell you if it's something about which to worry.

How many koi do you have?  Are they all 6"?  How big is the tank?  When koi don't move and lay on the bottom, it can be an indication of various things such as boredom, exhaustion/resting, illness, poor water quality, cold temperatures, etc.  If the tank isn't that big, that may explain it.  I would check your pH, hardness, ammonia, and nitrite to be sure those are ok.  I suggest doing weekly partial water changes and adding dechlorinator and aquarium salt (a tablespoon per 5 gallons).  I hope you have plans for a nice pond for them in the future!

Good luck!

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QUESTION: I had ywo butterfly but 1 died in a very weird way tail down lips up stright like it was pointing staright up....now have a 1" comet & a 7" solid red/gold shubukin in a 35gal. have another 55gal in reserve for when they get bigger then eventualy hand them over to a friends pond always change the water used to once a week now every other week because the ph was gettin lower with each change also have amonia rocks in the filter because that was very high but now all is balanced out 7.4ph & no amonia both tanks are clear also have a pleco very small in the 35gal bout 1/12"..do the ph tests & amonia gonna try the salt but do thinks its exhaust that they linger on the bottom there very active during the day & at nite my butterfly koi's (oden) his wings ar fully spread open always he loves darting thru the water comes up to eat he & the shubunkin(big red)seem to be bonded always along side each other especialy when resting on the bottom the lil red top comet (marie) is a loaner any suggestionsbe appreciated on how to keep better care or foods to use ect...

Answer
So, you have a 35 gallon with a 1" comet goldfish and a 7" shubunkin goldfish, and a 1/2" (surely not 1/12") pleco?  What about koi?  I thought you had at least one in there.  I suggest testing the pH and ammonia in the tap water to see if they are part of the problem if water changes make things worse.

It's normal for goldfish and koi to sleep on the bottom at night but they should be pretty active during the day.  The pleco is active at night, sleeping during the day.  I hope he doesn't take advantage of the sleeping koi and his/her beautiful fins to suck on them.  Small plecos sometimes suck on the sides or fins of larger goldfish and koi.  If he were doing that, you would see some skin or fin damage.  I suggest any good goldfish, koi, or pond food.  Tetra goldfish flakes are good for small fish.  Hikari goldfish foods are fancier.  My fantails get Oranda Gold by Hikari.  Plecos can eat sinking algae wafers.  My page on plecos is at http://www.fishpondinfo.com/pleco.htm