Check EVENTS daily for "NEW GALACTONITE TYPE." See the screen shot below. As you know, Galactonite energy is needed to upgrade your Galactonite "rocks" or "crystals" ... and you need a LOT of it. Every so often the game allows you to use "CUBITS" to compose Galactonite energy when you are also producing the Galactonite rocks. Sometimes the game tells you you can produce this energy, and sometimes they do not announce it.
HOW TO MAKE GALACTONITE ENERGY. When you are given the opportunity to produce Galactonite Energy (and you have a lot of credits), go to the GALACTONITE CENTER (below). You can simply click on COMPOSE. Most of the time you will produce rocks (sometimes called crystals) of Galactonite. Once in a great while you will produce the gold colored, multi-pointed Galactonite Energy rock. In the screen shot below I have 7 of them. To turn the Galactonite Energy gold colored crystals into Galactonite Energy you must be in the GALACTONITE CENTER (see below), and in the LABORATORY. Click on one of the crystals, then chose to decompose it. Each crystal gives you 500 Galactonite Energy.
You usually have to produce a LOT of Galactonite before you can "win" any energy. To speed up the process I click on AUTO COMPOSE and also click on AUTO DECOMPOSE and set the decompose to R-3 rocks and lower. (I am at level 88 and am acquiring rocks of R-5 and higher.) See the screen shot below to see how I mass produce and decompose rocks, When you select AUTO COMPOSE, the Galactonite Center will compose Galactonite rocks to fill up all your "empty storage spaces" in your laboratory. Mostly it will make R-1 and R-2 Galatonite, and perhaps an R-3 and/or R-4. If you are collecting any of these, change your Auto Decompose to whatever you don't want saved (if any). REMEMBER, you can REFINE as much R-1, R-2 and R-3 Galactonite as you want at any time, so if you are just starting the game you may want to Refine the lower Galactonite rocks that you get.
I find, that on average I have to spend about 1 million cubits to get two of the Galactonite gold colored crystals (in screen shot below). Each of these can be converted to 500 units of Galactonite energy. So, on average, for every 1 million credits you spend you can earn around 1,000 units of Galactonite energy. (Sometimes you will get more than 2 crystals, sometimes less. I have found that I have to spend 1-2 million credits before I even start to get the Galactonite energy! This is why you may want to use AUTO COMPOSE. Because you have to make so many rocks BEFORE you start winning the energy, it's faster to mass produce the rocks and to mass decompose the ones you do not want.
I also use the AUTO DECOMPOSE for R-3 rocks or less because I don't need them and it's faster to just have the computer decompose them then to do it yourself one rock at a time. You will get "back" some additional Galactonite Energy when your decompose the rocks you don't want AND you will get back some of your credits.
Because Credits are about the easiest things in the game to collect, if you have some extra credits I find a good use for them is to produce the Galactonite Energy.
HINT: You may wonder why I have so many Credits? When you reach certain levels in the game (like between 85 - 90 where I am now), you go for long stretches where you have upgraded all your buildings, etc. (the items you need credits for). So you amass large quantities of credits. You don't want to use them all however! Once I reach level 90 I will have to upgrade all my buildings AND do upgrades on my ships. At level 90 these require a LOT of credits to accomplish. So, you want to save a lot of your credits for future expenses.
HINT: Eventually you may reach a point where your storage for your Galactonite Rocks gets full, or almost full. If this happens you can actually free up storage space in the Galactonite Center by placing your extra rocks in your fleet ships that you are not using. I have used Leptons to purchase the cheapest, weakest ships I could find and use them to store my excess rocks. Each ship can hold 8 rocks. Five ships can hold up to 40 of your rocks and free up a lot storage space in your Galactonite Center.