Creating a Tank for Natives (Part 2 in a 3-part series)

Part 2: Medium to High-Current Species Tank

By Brian Torreano
First published in Splash, Milwaukee Aquarium Society
and on Brian's website about North American native fish: www.btdarters.com
Aquarticles

Intro: Hopefully you enjoyed the last installment in the series, creating a slackwater tank for your natives. In this installment I will be describing how to create a tank for our native species that live in medium to high-current areas of streams and rivers. You will notice in this article that some of the species that were included in the slackwater tank section are also included here. That is because those species occupy multiple habitats. In this section, I will be placing less emphasis on the fish that occupy different levels of the tank. A good rule of thumb to follow is that Blackstripe Topminnows live in the surface zone, most other minnows live in the middle zone of the tank, and the darters occupy the bottom of the tank. Although I will only be discussing natives, the setups described here can also apply to non-native fish that live in similar environments. Also, all of the fish I will be describing here are community fish, so they can be kept with just about any other community fish. The tank setups in this article will be good for a combination of any or all of the following fish: Rainbow Darters, Jumbo Rainbow Darters, Fantail Darters, Logperch, Sand Shiners, Common Shiners, Bluntnose Minnows, Spotfin Shiners, Suckermouth Minnows, and Blackstripe Topminnows. Because the creation of current in the tank depends a lot on the shape of the tank, in this article I will be discussing setups by tank size and shape. One important thing to keep in mind with these setups is oxygenation. Having an extra airstone in place in case the filters or powerheads fail is never a bad thing.

Easy 10-gallon setup: The standard 10-gallon is probably the easiest medium to high-current tank to set up. All you need is some substrate, some rockwork, some plants (if you want), and a powerhead. Substrate should be pea gravel or Turfacer® . Any powerhead with a sponge prefilter can be used; I have had really good success with the 170 Gallon Per Hour Penguin Powerhead with Sponge Prefilter by Marineland. Do not worry about "blowing your fish out of the water". With the medium to high-current setup it is better to have too much current than not enough. As far as heat created by the powerhead is concerned, I have never had the Penguin powerhead overheat any of my fish. Plants I have used with good success in this setup are Naias grass, Pygmy Chain Sword, Amazon Sword, Anacharis, Bacopa caroliniana, Cryptocorene sp., Java Moss, and Java Fern. All of these plants were grown under standard aquarium lighting.

To get started setting this tank up, fill the tank with about 2 inches of substrate. Then add the rockwork and plants. Add the water to the tank. If possible, use hard water as most of our natives come from a hard-water environment. Then you will want to attach your powerhead to the side of the tank. The powerhead should be positioned so that its flow goes down the long side of the tank. The Penguin powerhead mentioned earlier has the option of using either a suction-cup to attach it to the tank or a mounting bracket. I recommend using the mounting bracket as the suction-cup has a tendency to lose suction and the filter drops to the bottom of the tank. If you use a standard hood on the tank, this will mean that you will have to leave the hood open a little bit in the front to accommodate the bracket (I have only ever had a few fish jump out of the tank with this setup). Then add the airstone (if you want) and the fish, and you are all set!

30-gallon setup: For the 30-gallon, equipment is pretty much the same as the 10-gallon. You will need substrate, rockwork, driftwood (if you want), plants (if you want), one or more powerheads and/or an external filter, and lighting. The lighting you choose will depend in part on the method you use to create current in the tank. If you choose to create current by placing an external filter (such as a Penguin Bio-Wheel filter by Marineland) on the short end of the tank, you will have to use lighting that is either mounted on the back of the tank or suspended above the tank. I believe Hoffer’s carries mount-on-the-back setups. For suspended lighting, you will want metal halide lights. I’m not sure if Hoffer’s carries these, but you can find them on the internet if you do a simple search for "metal halide aquarium lighting". If you choose to create the current by using one or more powerheads mounted on the short end of the tank, be sure to get powerheads with a low heat rating. You will want to use powerheads with suction cups so that you can mount the powerheads in an array (I will explain more about this in the next paragraph). An array of Power Sweep® Powerheads by ZooMed might create a very interesting effect.

To set up, start again with about 2 inches of substrate. Add the rockwork and plants. Add water to the tank. Now add your filter(s)/powerhead(s) to create current. As in the 10-gallon setup, you want do direct the current down the length of the tank. If you are going to use an external filter, mount it on the short end of the tank. Otherwise, to create an array of powerheads, mount the powerheads on the short end of the tank and place them horizontally, instead of vertically. Stack the powerheads one on top of the other to create a lot of current. As in the 10-gallon setup, you may want to add an airstone for insurance in case the powerhead(s)/filter(s) fail. Add the fish, and set up your lighting, and you are all set!

Bow Front Setup: For the bow-front aquarium, we are going to use the same materials as the 10 and 30-gallon setups. The only difference is the type of powerhead we are going to use. For a small tank, such as a Mini-Bow 5™ by All-Glass Aquariums, you will want to use two small powerheads such as VA-80s by Via Aqua (I believe Aquatics Unlimited on South 108th Street carries these). For a larger bow-front, you will want to use larger powerheads.

To set up this tank, start with about 1½ to 2 inches of substrate. Add the rockwork, water, and plants. The rockwork should be placed in the middle of the tank (See Figure 1) so that the current will flow around it. Plants should be kept to the sides and rear of the tank. Be sure not to block the flow from the powerheads. The powerheads should be placed one on top of the other on the back glass of the tank and to one side (again, see Figure 1). This creates a really neat circular flow in the tank. Add the fish, and you are all set!

Hex Tank Setup: For the hex aquarium, we are going to use the same materials as the previous setups. The difference, again, is going to be the types of powerheads we are going to use. The brand of powerhead is not particularly importand, but for this setup the powerhead(s) will need to have directional-flow nozzles and suction cups for mounting. Again, try to get powerheads with a low heat rating. I would also recommend powerheads with prefilters because extra filtration is never a bad thing.

To set up this tank, start with about 2 to 3 inches of substrate (depending on the size tank you have chosen). Add the rockwork, water, and plants. The rockwork should, again, be placed in the middle of the tank so that the current will flow around it. Plants should be kept to the sides and rear of the tank. Be sure not to block the flow from the powerheads. The powerheads should be placed vertically and staggered along the back glass of the tank (see Figure 2). Be sure to turn all of the flow nozzles in the same direction to create the circular flow in the tank. Add the fish and you are all set!

Conclusion: In all, constructing a tank for medium to high-current preferring natives is relatively easy. The important thing to remember is to keep the water moving. For pictures of the fish described in this article, or for more info., please visit my website at: http://www.btdarters.com or email me at info@btdarters.com. The next installment in this series will cover setting up a tank for species that like to live in heavily planted conditions. Until then, happy fish-keeping!

Go to: Part 3, The Planted Tank