Re-mineralizing water?

[SugarBassJoe]

So, I recently got lucky with finding a few more fish id like to try breeding, but my water is quite hard, comes out of the tap around 400+ ppm., so I decided to go ahead and spend the money on a simple RO filter. I haven't installed the deionizing filter on it, but the water coming out of it is consistently reading 14-17 ppm., which I know is very low. I thought about mixing it with tap water to raise levels, but I was thinking it might be easier to raise the hardness levels by other means if necessary, wonder shells. neutral regulator, something like that. I have one 20G tank setup with just RO water, and I've been slowly using it for water changes in the other 2.

According to ACP test strips, parameters in the RO only tank are:

Nitrates-25

Nitrates-0

GH-17

KH-0

PH-6.4

So I know it will depend species to species, but I've never messed with RO filters before and I know there's a lot of admirable breeders on here, so I wanted to ask all of you, since I can only really find general info on water conditions for the fish I'm currently hoping to breed. The 3 species I'm currently keeping and hoping to spawn are Apisto. Agassizii ( just got a group and was lucky enough to have M/F pair up), Gardneri killifish, and a hybrid strain of Rams (electric blue/black ram, though I don't think that will change anything specific). I've had very low success with egg laying fish in the past, they'll try, but haven't had any amazing spawns from them and I'm pretty certain its has something to do with hardness of my water.

Just hoping for some advice, tips, things to look out for, things of that nature. Thanks ahead of time for any help.

[Fish Folk]

As long as you keep the water reasonably consistent across water changes, your plan can work.

Your Rams are just a color morph cross, not a biological “hybrid.” They’ll appreciate soft water. I personally pull Ram eggs and let them hatch in a floating flow-through container. I can explain more if you want. Rams can learn to raise their own fry, but after watching many pairs eat their own eggs, wigglers, and fry, I prefer to pull. Maintain common water — I pull and keep in the same water they spawned in. Rams like temperature around 80°-F.  I find they get ill if I feed too many bloodworms.

Gardneri killis probably do not _need_ super soft water. But they can adapt to a fairly wide range of parameters. You don’t need a heater, IMHO. Throw in a few spawning mops, and feed them well. Males can be brutal to females sometimes.

Apistos will appreciate leaf litter, botanicals, and several caves to spawn in. Soft water is fine. I advise against pulling eggs. Female Apistos can be marvelous parents.

[SugarBassJoe]

Thanks  Fish Folk, I will be on the look out with the Rams, I have seen them spawn, but no fry has come yet, that would be a good explanation as to why. I haven't seen much spawning behavior from the Killi's yet, might be to young still, though I don't know the age of them, biggest male might be an inch and a quarter. Goin to be moving the Apistos. over to the empty tank soon, don't have much as far as botanicals, but I've got caves covered. Appreciate the insight, thanks again!