About minerals in the water

[rkeane]

Hi all,

May tap water is hard - TDS can go up to 250 with pH 8.0.
For my breeding pair, I used 50-50 RO-tap mix and was able to bring the TDS down to ~90-100.
The pair is now having ~50 fry at their age of 8-day old.
I am just curious if the TDS 100 water would be able to supplement them with enough minerals for their growth?
Or should I slowly increase my tap %?

Thanks,
P

[AquaticNerd]

I don't recall exactly who on here recommended this (perhaps CliffsDiscus or Willie?), but I do vividly remember that after hatching they said that they put them in 100% tap without the need for slowly increasing TDS.

[Willie]

The need for minerals in the water is a myth perpetuated by manufacturers who sell these additives. In the Amazon, millions of discus fry grow into beautiful fish with TDS < 5.0. There's no harm in doing so, but you'll see far better growth with just frequent, large water changes. In fact, adding these additives is not possible, or at least incredibly expensive, with large water changes.

[RogueDiscus]

Willie can correct me if I get anything too off-base
I keep all my fish in my well tap water with about 480 ppm and pH 8.2.
When I was breeding, I used RO to drop the hardness to around 50 ppm. I think the pH changed a bit, but not much. Still alkaline.
After the fry were hatched, probably free-swimming, I returned to using my hard water for water changes. Perhaps gradually, but not very.
All living things use minerals in their energy conversion processes, but given the low mineral content of their natural environment, I suspect healthy discus get what they need from good food rather than the water. That said, I worked off the advice of another long time member here and water guru (sorry, old-timers) who suggested something like up to 180 ppm could be beneficial for developing fry, but that more was OK but made no difference. It was easy for me to just add back in the well water.
Producing the RO I needed was the pain
Steve

[LizStreithorst]

Willie is right.

[RogueDiscus]

And there it is.

[matt parsons]

So 15 years ago or so I tried raising my fry in my waste RO water to up thr TDS. My source water was around 200 tds which, I always put the fry on once the were free swimming. But I thought why not increase it with all this water I’m just wasting. I ran a constant drip on my breeders so the waste water would do constant water changes. It worked very good. I can’t say I saw better growth than before for certain, but I believed it did improve. It may have just been the huge increase in water changes. Either way I kept it going until I shut down my fish room.
Im a big believer in giving the fry straight tap for two reasons. It’s easy to consistently provide and I think the minerals in the water help in development.
Respectfully, Matt

[LizStreithorst]

I add my RO waste in the storage container that contains mostly pure tap. It's not because I find value in the minerals. I'm of the belief that fish get their minerals from their food rather than their water. I just see no reason to waste it.

[CliffsDiscus]

I don't recall exactly who on here recommended this (perhaps CliffsDiscus or Willie?), but I do vividly remember that after hatching they said that they put them in 100% tap without the need for slowly increasing TDS.

Yes, I move the eggs around a hour BEFORE hatching to straight tap, this can shave off
time, then before free swimming I start culling out some of the deformities just
like what the parents would do.

Cliff