Wednesday, July 18, 2012

Setting up 20 gallon tank

I recently helped my 10 yr old son set up one of my old 20 gallon tanks. He wanted an aquarium of his own. In the past, the tank had been set up as a salt water aquarium which housed a couple of clown fish. The clown fish are gone now, but the tank still had ocean reef sand, heater, skimmer, etc. in it. Lot's of cleaning to do. The inside of the glass was also covered in hard water deposits and scum. So, what are the steps in converting this tank into a fresh water aquarium?

1.Remove lid, light fixture, heater, skimmer and any other equipment from the tank. Clean all of these items and inspect.

2.Remove sand using small plastic cup. You may have to use your hands to remove sand from the corners.

3.Fill tank with water and 1 cup of white vinegar. The vinegar will loosen the hard water deposits. Allow tank to sit for 1 or 2 days. In a couple days the mineral deposits on the glass should start to loosen.

4.Drain the tank using a siphon hose or small pump. You can also use cup or small bowl and dip the water out into a bucket.

5.Rinse tank. I took mine outside and rinsed with garden hose. You could also put into bath tub and rinse. Tip the tank onto one side or end while rinsing. Be careful not to scratch or crack the glass. If this is too difficult, just rinse with tank on aquarium stand and then siphon out dirty water.

6.Put aquarium onto stand. Make sure it is level and solid. Stand must also be able to hold weight of filled aquarium. Remember, water weighs 8.34 pounds per gallon.

7.Add aquarium gravel. 1.5" in depth.

8.Slowly add tap water. You may have to re-level your gravel later since adding the water will stir up the gravel a bit. After filling the tank about half way, you can start decorating with artificial plants, rocks, drift wood, etc. Also at this time you can install heater, filter and or air pump with hose. I always run air hose down the back of tank and then hold down the end with a large rock or drift wood.

9.Continue filling. Don't over fill to the point that placing your hand and arm into tank to arrange decorations or whatever will disperse water over the top. Check this before getting the tank completely full.

10.Place lid and light on top and plug in heater, filter, air pump, etc. Make sure everything is working. Allow the tank to operate for a couple days and the water to stabilize to proper temp. I keep my fresh water tanks at 75 to 78 degrees F.

11.Add a few hardy fish and allow tank to cycle. Check below to my previous post to learn about cycling a tank.


  1. Hey I was wondering if you raised Angel Fish. I know a guy named Dean that raised angelfish in Onawa Iowa. I have Two 55 gallon tanks. I was interested in maybe buying a few.

  2. I am raising tilapia. Experimenting with some Aquaculture.