I guess I am differrent then the rest of you.
Modified t line I guess, I use an old ehiem canister filter I had for about 20 years. I added 2 t cup-links to the loop with a shut off valve in between, on the t side of the lines I put them thru an unused slot and add shut off valves to each. To fill it I pour the coolent into the ehiem attach it to both shut off valves. start the ehiem and open the valves, roll the case a few times to get out all the air and then pressure test the whole loop. If it doesn't leak, I shut the valves and take off the pump, ready to use. To drain I just turn off the ehiem and upright it and roll the case around a few times to let it drain out by gravity. Whole process takes about 5 min to fill, leak test, and drain if need be.
Modified t line I guess, I use an old ehiem canister filter I had for about 20 years. I added 2 t cup-links to the loop with a shut off valve in between, on the t side of the lines I put them thru an unused slot and add shut off valves to each. To fill it I pour the coolent into the ehiem attach it to both shut off valves. start the ehiem and open the valves, roll the case a few times to get out all the air and then pressure test the whole loop. If it doesn't leak, I shut the valves and take off the pump, ready to use. To drain I just turn off the ehiem and upright it and roll the case around a few times to let it drain out by gravity. Whole process takes about 5 min to fill, leak test, and drain if need be.