IMO the Krobia probably wouldn't spawn in that water. I have a similar pH with lower gH/kH and they would only court one another. Peter's pH was in the 6's and they spawned not long after he got them.
Pelvicachromis species' sex ratios are often affected by pH. Depending on the water you raise them in, you may have a shortage of males or females. If I'm not mistaken, P. taeniatus would need a neutral pH of 7 to get a fairly balanced number of males and females. Some fish, like E. lucanusi, seem to spawn in softer water with a lower pH, so I haven't figured out yet what that means for their fry. I guess I'll cross that bridge when I get there.
I'm assuming HRP, if they're anything like convicts, will spawn in that water.
Do you think the krib's offspring would be very far off in gender balance with the pH being only a few points higher than 7.0?
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