My poor pleco

Question
QUESTION: Tank size: 120 ltr
pH: 6.4 (was 7.2+ but tonic requires 25% water change)
ammonia: 0.1 give or take
nitrite: 0 mg/L
nitrate: 0 mg/L
kH:
gH:
tank temp: 26-27*c

OK, so lately last 3days i noticed my pleco wasnt looking
so great.
straight away i started the tank on a treatment of wunder -
Tonic.
but i thought i would get some advice.
My pleco sort of hangs around the bottom of the tank, just
doing next to nothing.
normally he would suck around (as they do) then when you
walk up or past the tank, he'd swim away and hide in his
rock.
but lately he sort of just stays there looking at you. fin
down, sad like.
i noticed that he looked very skinny, his stomach is sucked
in looking. so i put a couple of pleco drops in and kept an
i on him.
i notice he did go up and have a bit of a feed but not
much, then went do his rock again.
i've notice a bit of a dis-colouration on him, so i put
some tonic in the water.
i also put some cucubumber in and he had a munch.
he use to always swim up to the top of that tank and eat
the fish flakes, but now he doesnt do that either.
i do have some photo's.
I had another look closer today, he was near the glass, and
it looks like Ich. although im not 100% its like tiny
little glassy looking dots. im talking, pixel size!
I've just done a water change and put some tonic salt in
the water.

nothing new to the tank really, ph tested tap water and its
around 8.0+ so i did a 25% water change and checked the
tank, 6.4 after the change, was 7.6 but it always been
around 7.2
added a couple of planets about a week or so ago. maybe 2
weeks.
been told water in Tauranga - New zealand is really high at
the moment, pet store told me.

OOhh, i also recently like tuesday put a new heater in
because I thought there was a leak, as it had water in it.
and i did a check and was getting 60+ volts AC from the
water. (outlet power is 240vac)

sigh, my poor fishy.




ANSWER: Hi Chris,
Your PH is fluctuating, and that can damage fish.  Try to keep them in the same PH, going from 8.0 to 6.4 then to 7.6 is really bad for your fish. To keep your water down to 7.2 you would have to buy peat or water softeners to keep it down....but if you have water problems and your local water is at 8.0 you can buy fish that like hard water.  Your pleco can get use to 8.0  if it it always at 8.0.  It is easier to keep it alkaline.  You can buy or maybe even find rocks that would make your water alkaline, and keep it at 8.0 always.  Sea Shells that are clean, can be put in the aquarium.  This will bring up the PH.  Be careful though  how many you put in.  Put some in and the next day check your PH, if it isn't high enough, put some more in and wait a day, and check again...and so on until you have a PH that will always be the same.
 I think that your Pleco isn't getting enough to eat.  People think that they don't have to feed them, that they will find food, but this is untrue.  You must feed him just like you would any other fish.  The Pet Store has special food for them, I hope it isn't too late for your Pleco.  Poor thing!  Disease comes quickly to fish that are poorly fed.  The pet stores don't always tell you this, but you must feed your fish 3 times a day.  I had 27 aquariums, never had diseases, and fed my fish 3 times a day, and sometimes 4...fish must eat, and have different menus.  They must have 3-4 different kinds of food.  The Pleco must have one...it is flat pellets that sink to the bottom.  If you buy large ones made by Hikari, you will need to give him one everyday. (Don't give him three a day) one a day for the pleco.
Ick looks like salt, The Pet Store has medication for ick.  It is fairly easy to cure if caught in time.  There are many products for the cure, and all work fairly well.
Hope this helps
Lynda

---------- FOLLOW-UP ----------

QUESTION: Thanks again, thats was the most informative and helpful answer i have got from anyone! A++

Is there anything i can do to help him?

ANSWER: Hi Again Chris,
Getting him to eat now would be the most important thing you can do... They like cooked spinach, lettuce, but if you get him the pellets, that would be great.  They also like to suck on driftwood, so maybe you could get him one.  Pleco's are more active at night,  drop food in when the lights are closed.  If he has ick, you will have to cure him with "ick cure", or some other medication especially for ick.  You can google it too...just put in "Pleco Fish" and it will bring you to some sites, where you will find lots of interesting things on Pleco's
Hope he recovers, Good Luck, and thank you for the compliment.
Lynda

---------- FOLLOW-UP ----------

QUESTION: I put a algae drop right in front of him and he started having a nibble/suck, went out quickly to the bp and did my partners tyres and came back and he was still at it, do they normally eat the entire thing in one sitting? or is it sort of suck swim away, come back have a bit more deal?
the reason i ask is my fish absolutely love these drops aswell.
thanks again Lynda!

Answer
Hi!
Plecos will keep the pellet, and eat it all in one sitting, you will never find bits of pellets left uneaten...but if your fish like them too, maybe he is a little afraid to keep one and finish it.  It's like "who is going to get this down first!"  lol  Observation is the key.  Maybe there is a fish he is afraid of who takes away his food!  You didn't mention what kind of fish you have, so I don't know.   
I'm happy the poor thing can still eat.  Make sure he does, even if it means giving him tripple dose.  When the lights are out, and the fish are sleeping, that's when you should feed him...Plecos are night fish, they swim around the bottom at night looking for food.  Remember that your Pleco is very weak now, and probably cannot compete with the fish for food.  Make sure he gets his share, and give him more than his share, until he is plump again.
Hope this helps
Lynda