Water & Gravel
 


Water

Killies are from all over the world and following it is difficult to say much generally about the best water for killies. We are lucky in Scandinavia that we have pure and clean tap water without chlorine or other assets. The water here is about PH 7 and about 15 DH hardness. Many killies are ok with these conditions and you will be able to breed many killies under these conditions. Remember when dealing with PH that one step on the scale is 10 times more acid/alkaline. So if your fish is best at PH 8 and you give them 7, it is ten times more acid than the perfect water. So jumping up and down if PH can be very fatal for your fish. If you are new to the aquarium hobby I suggest you to choose fish that suits your tap water. There are many more interesting thing to spend your time on than preparing water.

If you anyway have to change the PH and DH there are many solutions. Some hints are:

Goal
Suggestion
Softer + a little more acid
Use rain water which is very soft and slightly more acid
Softer + more acid
Put some rain water into a bucket and take a hand full or 2 of peat into a nylon panty hose. Put the pantyhose in the bucket and leave it there for 14 days. Then you will have extremely soft and very acid waters. Mix it eventually with tap water to get the right condition before pouring it to the tank.
A little more acid
Adding co2 to your tank will lower the PH a bit. This is though quite difficult to manage precisely as the plants will use the CO2 in the day and produce it in the night. It can be hard to control the PH effect on this with constant co2 adds. But a good side effect is that you plants will love it - especially if you have aeration of your tank which will take out co2 from the water. (like shaking a cola)
Much more alkaline and harder
Buy a PH buffer from your local fish store. Mix it in water OUTSIDE the tank and be very careful with the buffer.
A little more alkaline and hard
Take some chalk stones into a big bucket or container. Fill it up with clean tap water and leave it for 14 days. Mix it eventually with tap water to get the right condition before pouring it to the tank.

If you are new to the killies all this water preparations could might scare you but do not be afraid. There are so many beautiful killies and I am quite sure you will find some matching your tap water. Actually this water issue is not only important for killies but also for all other aquarium fish. They are like us humans born to fit the habitat of their species.

Caution note: When using collected rain water then think twice about your surroundings. If you live near a large industrial zone the rain water would might be polluted and not suitable for aquarium use.

 

Gravel

Many killi keepers do not use gravel but have bare tanks. There are a few advantages and disadvantages of both solutions. Gravel makes you able to choose between a lot more plants. It looks very pretty and has a build in bio filter. After a period the bacteria in the gravel will help the break down of the debris and provide the filter a helping hand. But you will at the same time also get a harder job to collect eggs from annuals as well as suck away uneaten food to prevent water pollution. I started using gravel for my non annuals but have now changed all my tanks to bare because it is much easier. I do not like the clinic look of a bare bottom but I try to look at the fish instead and enjoy that the eggs are now placed in my mops or plants instead of in the gravel. If you choose to have gravel all kind of gravel is possible. A good idea is to make sure that the gravel will not contain chalk or other PH changing ingredients. Another issue is that some gravels are quite sharp. The female could get hurt when trying to spawn in a sharp gravel so I would choose rounded gravel.

Many keepers with bare tanks use peat as substrate especially for annuals. But as you can read above, peat makes water more acid. To avoid this you can thrive out the effect by placing the peat in water for 14 days or longer. If you miss the patience you can also remove the acid making effect by boiling the peat in clean tap water. After a few hours of boiling you will minimize the acid effect. The benefit of using peat is that you can collect it all from the bottom and be sure that you have all eggs here. (if not other spawning objects are found in the tank).