I'm sorry this will be long. I tried to answer all the questions from the Fish health diagnostics sticky.
Size: 150g freshwater
Filters: 2 HOB- 1 is Fluval 110 and other is Whisper 30-60
Heaters: 2 Marina 300 W. Water temp is 82°
Plant: 1 LG very deteriorated sword plant. This is kept as a cushion when sharks spaz and slam into glass.
Fish: 2 Iridescent sharks. 1 is 16" second one is 14" (this is the fish in question)
1-10" common pleco
4- 5" hybrid synodontis
3- phantom tetra
2 - flame groumies
1- golden groumie
5 or so guppies. They keep breeding but the tetra and groumies keep them in check
Also 8-10 nerite snails. Few have passed recently so not sure of exact count.
I have a gravel bottom that is vacuumed at every WC.
Parameters are included in pics. I use just simple test strips and a sechem ammonia test. Params are at the same level they usually fall at. Pics included but everything checks out normal. I use city water for wc every 11 days using Prime. 30% changes are done.
This particular tank has been running for 4 months. Originally I had a 55g and then upgraded. When I transfered tanks I moved all the used gravel and decor including the Whisper filter that I transferred unscrubbed/unwashed.
Food: ID sharks eat New Life Spectrum Mega Fish Formula, once a day probably 10 pellets each.
Pleco eats Hikari Algea Wafers. 4 each night
Other fish eat Tetra brand Tetra Tetra min tropical flakes. One pinch a day.
The shark in question also has pics included. He is covered in white patches (definitely not ich) these started about a week ago. First only a few on one side then gradually more and more patches. These patches look more like an injury knick would almost like scuffed skin. Again it's definitely not ich. No other fish show any signs of this and the larger shark has smooth skin as always. The questionable shark is as active as normal and still eats great. He can be seen rubbing along the gravel bottom. I wouldn't say excessively but probably seen 3-4 times a day. I do have 2 pieces of decor, a small log and a medium fake rock formation that conceals my air bubbler. Both can be seen in my full tank shot. Although it is not impossible for the shark to run into, I would say that it's unlikely. They sit to the back of the tank and it's nothing that I have personally seen either of them do.
Thank you in advance for any help we receive. I love these sharks and have plans to put in an indoor pond for them when they start to outgrow the current tank. I just want to be sure and help him fix whatever is wrong.
Thanks again - Amber