I have a 120l tank which is home to 6 cherry barbs, 6 amano shrimp and 6 harlequins. The tank has been established for about 3 years now and seems to be nice and stable. It gets a 10% weekly water change, and is filtered by an eheim 2222 external.
I've been thinking about adding some more interest to the tank and I quite fancy a couple of Bolivian Rams. So my first question is assuming water chemistry was correct would my setup be able to handle the addition of two Rams?
Right, next question is regarding water chemistry. The water in Oxfordshire is pretty hard, according to Thames Water is is 16dh which according to the care sheet is too hard for the Bolivians (I've not measured my own water yet). Also, the pH of the water in the tank is 8, so again this is not appropriate. The Goldfishbowl shop up in Oxford offer free RO water at the moment (I think, they did last time I was there a few months ago) and I'm wondering on the viability of gently changing the chemistry of the water over a period of time using RO water (perhaps mixed with some tap water, or additives?) and maybe using some peat moss in the filter. Am I barking up the wrong tree with this idea, or could this work well?
One thing I won't do is risk the well-being of the current inhabitants. If they're not going to like it then I won't bother.
Any advice or general thoughts would be gratefully received!
The fish you have now will appreciate softer more acidic water but the shrimp won't. So, I would be inclined to either rehome the shrimp or set them up a new tank with dechlorinated tap water and use RO for the fish you have. You will need to change the water quite gradually and you are right that you can't use raw RO, you need to add some minerals to it. That idea sounds perfectly viable
Not sure on tank size requirements for rams but I would have thought 120 litres would be big enough. I will check with our cichlids adviser
its possible but you would need to read up on the water chemistry guides on this site and have a very good understanding of what you are changing and why the it would be a very slow and gradual change over quite a few months
The water should have a PH of 6.5 and a dGH of 5. So in order to keep Bolivians, or any South American Cichlids, Dwarf or otherwise, in your tank you will need to use 100% RO water to get your PH and hardness down to that level, and keep using RO every week for water changes, remineralising the water to suit the rams. This will take a lot of experimentation to get the results right. You will also need to add bogwood to add tannins to the water that is required by these fish, and it will also help to soften the water. Rams need a tank that is well planted, with plenty of hiding places. The peat moss in the filter will also help a little, but it is a little too unstable to use as a buffer on its own, especially at levels you are working with. Rams need very precise water conditions and do not like any changes, no matter how small.
In order to bring down the levels with the present occupants in the tank it is going to take months so as not to cause PH Shock or any other problems caused with reducing water PH and hardness.