This is a discussion on Water change with bubble nest? within the Beginner Freshwater Aquarium forums, part of the Freshwater Fish and Aquariums category; -->
I picked up 3 gallons of R/O water from walmart in a jug i can fill up and just drain out the bottom on ...
I picked up 3 gallons of R/O water from walmart in a jug i can fill up and just drain out the bottom on top of my filter to not disturb my plants and I would like to know if its safe to attempt a 6 gallon water change by siphoning out tank water from one side and refilling from the other side and attempt to keep the water level at the same place.
My issue is that I have a male golden honey gourami guarding a bubble nest as well as harlequin rasboras spawning under leaves and my ph is around 7.5 and I would like it closer to 7 to help the fry of both species. But I don't want to shock either of them and I really don't want to risk destroying the bubble nest.
Option A - Wait a few days until male stops guarding and let the harlequin spawn die in the high ph ( might be too late anyways)
Option B - Attempt a water change now and "try" keep water lv from changing during change and run the risk of harming bubble nest but lower the ph to a safer level
The GH is more critical to eggs and fry than pH, due to the calcium. The partial water change with pure water would obviously reduce the GH, but I just wanted to note that the GH is the issue here.
I do my regular water changes regardless, and when I had some delicate gourami species spawning/guarding nests it didn't bother them. Just siphon out water from one side, and refill without disturbing the rest of the tank. The water level will drop but the floating plants will remain as they are on the surface.