The useless junk they try to sell you

pH adjusters. Sold to adjust pH (which is of very little importance to most fish) but either don't work (if trying to lower pH in hard water) or cause pH bounces and high phosphate levels and consequent algae.

water softening pillows - yes, they remove Mg and Ca ions so the water reads soft on the GH kit, but they replace each ion with two Na+ ions, so the Total Dissolved Solids is actually increased - osmotically, the opposite effect to what soft water fish actually want.
 
Good thread.:) Would terrestrial plants sold as aquatic plants count as "junk"?:naughty:

In the UK they'd count as contrary to the Sale of Goods Act - i.e. a criminal offence, if Trading Standards could be made to understand the issue.
 
The Artificial Decorations: Castles, No Fishing signs, Sunken Ships, and houses to name a few. Fish would like it better if you spend that money on a nice piece of driftwood, some artificial rock formations or plants more than a fake boat. Do you find these decorations at the bottom of the Amazon river or in natural pools in Southeast Asia?
 
The Artificial Decorations: Castles, No Fishing signs, Sunken Ships, and houses to name a few. Fish would like it better if you spend that money on a nice piece of driftwood, some artificial rock formations or plants more than a fake boat. Do you find these decorations at the bottom of the Amazon river or in natural pools in Southeast Asia?

I agree but try telling that to my 5 year old daughter! She "fell in love" with a totally hideous red dragon and my husband actually bought it! It's in her guppy tank and she loves it. The kid has no taste!
 
Cheap battery powered auto feeders...dump HUGE amounts of dry food into a tank TWICE a day...nearly killed my crowntail Betta in 4 days while I was away - moved him to my home (out of my office), gave him a starvation diet and several drastic water changes and I am happy to say he is very nearly in tip top form again and as much a character as ever! :)
 
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