Discus fry tank water hardness

[polar]

My Discus fry aren't growing like they should, and I'm thinking it's the water hardness. I've got a 40-gallon tank, 0 ammonia, 0 nitrite, 5 nitrate, pH 6.8, but GH is around 8. Should I cut it with RO water or just let it ride?

[Luckykeeper]

Hardness at 8 dGH is a bit high for fry. I'd recommend mixing 50% RO with your tap to get it down to 4-5. Keep temp at 86°F, feed 4x daily with live baby brine, and do 30% water changes every other day. They'll bounce back.

[Honey]

Hardness at 8 dGH is a bit high for fry. I'd recommend mixing 50% RO with your tap to get it down to 4-5. Keep temp at 86°F, feed 4x daily with live baby brine, and do 30% water changes every other day. They'll bounce back.

Agreed, but watch the TDS too. If it spikes above 200, they'll stall. What's your substrate? Buffering with peat can help stabilize things.

[foxcape]

Y'all making this sound like rocket science. My fry thrived in harder water, but I cranked the heat to 88°F and fed 'em blackworms like candy. Maybe yours just need a vibe check, polar.

[sealine]

I've had luck with a drip system for RO mixing. Set it up with a 10-gallon reservoir, airline tubing, and a valve to control flow. Takes the guesswork out. Also, what's your lighting schedule? Too much can stress 'em.

[polar]

Thanks for the tips, everyone. Gonna try the RO mix and bump the temp. Substrate's bare bottom, lights are on 8 hours. I'll report back.

[Silvan]

Bare bottom's solid for fry. Less junk to mess with. You got a sponge filter or HOB? Sponges are chill for bio, but HOBs move more water. Just don't let it suck 'em up.

[purered]

Y'all making this sound like rocket science. My fry thrived in harder water, but I cranked the heat to 88°F and fed 'em blackworms like candy. Maybe yours just need a vibe check, polar.

Heat's key, but blackworms can sketch out newbies. Stick with brine shrimp if you're not sure. Also, what's your water change routine, polar?

[LunaSky]

RO mixing is the way. I use a 3:1 ratio of tap to RO for my fry tanks, keeps GH at 4.5 consistently. Are you using any supplements? Calcium can help if you're cutting hardness too aggressively.

[chippy]

My fry tank's at 7 dGH, and they're fine. Maybe it's not the hardness. What's your feeding schedule? Overfeeding can mess with growth too.