water tds ppm.. how hard???

[cgrim10]

after recently adding salts to their water, and having made several partials since. the tank was at 400 ppm tds. a fish spawned the day before, so the water was harder then. i didn't expect the spawn to hatch. just dead eggs. well they hatched out about 40/50 wigglers today. and the ppm is at 270. whatsuppppp? aquarium salts raised the hardness to a point i don't let them regularly live. yet they hatched out.
how wierd.
cg

[brewmaster15]

Hi craig!,
Actually salts in general, don't raise the kH hardness, they raise the conductivity, and may raise the general hardness. The kh hardness is from calcium and magnesium predominately, and not found in salts. the exception is special buffered seasalts for marine tanks (they are designed to increase and hold a specific kH-- carbonate hardness)


many feel that it is the calcium and magnessium that is the problem with discus eggs not hatching.

awhile back there was even water softener pillows that were marketed and sold which exchanges sodium ions for the calcium ions/magnesium ions in the water. These were sold for use in discus tanks where soft water was wanted.


I probably didn't explain this well, but your TDS meter measures total Dissolved parts, and your salt boosted these, but they were not the parts that are commonly thought of as critical to egg hatching.

hth,.
al

[cgrim10]

i see grasshopper
nice to have a resident scientist isn't it.
so the gh general hardness is the dissolved salts ca/mg
and the kh is the carbonate hardness buffering capability?
nod if this is right. thx
cg

[brewmaster15]

close grasshopper...

you got the kH right but ...

http://www.fishdoc.co.uk/water/hardness.htm

Total hardness (general hardness) is the sum combination of carbonate and noncarbonate hardness of your water.
from...
http://www.netpets.com/fish/reference/freshref/discuswater.html

They say it better than i can. ;)
al