So on this blog, I’ve talked about building tarantula enclosures. This time we get wet.
One of my favorite parts of exotic animal keeping has always been the “build-out” phase. With fish, it is setting up planted tanks, usually for communities. This time I wanted to try my hand at a ‘species-specific’ tank, namely the Pea Puffer (Carinotetraodon travancoricus). This is a purely freshwater puffer fish from India, specifically endemic to Kerala and southern Karnataka in the Western Ghats of Peninsular India. In Kerala, it is known from 13 rivers (as well as estuaries), including Chalakudy, Pamba, Periyar, Kabani, Bharathappuzha, Muvattupuzha, Achenkovil, and Vamanapuram. It is also known from other freshwater habitats in the region such as Lake Vembanad and the Thrissur Kole Wetlands. (All links here courtesy of Wikipedia.)
My preferred method of building a freshwater planted tank is a modified take on what is called the “Walstad method“.
The ‘pure’ version is a self-contained wild tank that basically runs itself with the hobbyist just topping off the water, but this isn’t my objective, as these wild tanks are not as aesthetic as I’d like.
So I use some of the setups from that system and modify it to use some traditional aquarium techniques. What follows here is about four years of trial/error and watching a zillion youtube videos from those far more qualified than myself in this arena.
So let’s get on with it!
Step #1 Get a tank. In this case I’m using a 20 gallon ‘long’, which can be had at Petco for a dollar/gallon several times a year. (Outstanding value as the tanks are of decent build quality.)
Step #2 Procure the dirt, the ‘cap’ and any long term minerals/fertilizer that might be needed. The cap is gravel, sand or other material that will anchor the dirt in place below. The minerals/fertilizers are things such as Mexican potting clay, ozmocote or plant fertilizer tabs that need to be embedded in the dirt before finalizing the layout.
For “dirt”, you can get expensive and use brand name bags of pre-fertilized material, but I have found that basic organic potting soil from places such as The Home Depot or Lowes work beautifully. “Organic” as you DO NOT WANT additives which may be harmful to the animals that will inhabit the system.
Step #3 Lay about 1.5-3.5″ of the soil in the tank (sticking in the additives as you see fit). Compact and add more, sculpting this base as you go. It isn’t mandatory to keep it even. I prefer a taller amount of material toward the back of the tank with a gentle slope down to the front. In this case I’ve created a low hill to the right side.
Step #4 Once you have this situated, it is time to add enough water to just cover the dirt. This process allows the ‘floaty-bits’ to come to the surface for easy removal. Stuff that will clog things up if you leave them, such as wood chips and other material that ends up in the potting mix.
Leave this for at least a day before scooping out the muck. Then drain the water out as much as possible and leave it for at least two days to completely saturate the dirt. Resculpt and make sure the layout is right. I also create an ‘edge’ on the visible sections of the tank, pushing the dirt back from the glass by about 1/2″. When adding the cap material, this will avoid a two-tone appearance.
Step #5 Add the cap material. As a rule of thumb, make sure the gravel/sand/etc. isn’t too ‘fine’. The problem here is that the finer the material, the more compactified it will become, and you need the system to ‘breathe’. A compacted top layer means that the material underneath won’t be able to get oxygen for the bacteria that is going to grow there, and bad gas pockets can develop over time. This is not a good thing.
I’ve discovered that if you have 1-4″ of dirt below, have about the same amount of cap material above. This is not a hard and fast rule, but makes planting and maintenance easier for me.
Step #6 Time to get an idea of the surface layout. Rocks/driftwood/decorations. In this tank, I’m using pieces of pre-soaked spiderwood and a chunk of mopani wood. This will create anchors for floating plants and create breaks in the sight line which is important as Pea Puffers are territorial animals that will attack each other if they feel their ‘turf’ is being violated. Broken sight lines enable several puffers to call parts the enclosure ‘home’ and leads to a peaceful environment.
As an aside, it is VERY important to soak the wood for up to a couple weeks before using it in the tank. Wood that isn’t waterlogged will float, and that isn’t the idea here. You can also use fine string or fishing line to tie the wood to rocks to bypass the soak time.
Second aside. Using mopani, spiderwood and several other types of wood will cause tannin leaching for some time after the tank is set up. This is NOT a bad thing and in some cases the desired outcome. The fix is simply regular partial water changes. After several months, the tannins will have completely left the wood, and the water will remain clear. For some aquarium setups, the tannins create what is referred to as “Blackwater tanks”, and have a tea color to the water. To maintain this, several types of aquatic leaves can keep this going even after the wood is exhausted.
Step # 7 Once you have things the way you’d like, it is time to fill er’ up. A good trick to avoid a cloudy mess is to use a bowl/plate/cup to shock absorb the incoming water. In the picture I’m using a low tupperware bowl with a big rock (to keep it from moving around) to accomplish this. It isn’t required, but it will save a couple days time waiting for the things to settle out.
Another aside. In step 7, you CAN add plants before the fill-up. Some hobbyists do this, but in this particular build, the stuff I wanted wasn’t available until after, so I did the planting once the tank was filled.
Step #8 Plants. This can be whatever you’d like. In this build, I use some micro sword plants and java moss for the foreground/mid areas, and floating types of plants for the wood. Once things are settled in, I’ll probably add some anubias and maybe some dwarf swords to the mix. This piece of the build is an evolution as what you like at the beginning may not work out, or you change your mind. As long as you have them. Plants provide an enormous amount of filtration, oxygenate the water and will help kick-start the bio-cycle saving a lot of time if you don’t have any existing bacteria to pre-seed the tank with.
Step #8b Pea puffers don’t like much if any water current. So for this build I’m using two medium sized sponge filters using a good air pump connected to a gang valve to power them. In the aquarium game there are a zillion ways to filter a tank, but if you check with breeders and professionals in the hobby, THIS is the preferred method by far. Simple cleaning maintenance and the sponges will last for years and years.
Step #9 Adding the fish. I’m NOT getting into acclimation and such here. There are many ways to safely add fish to a new tank, and about as many videos/tutorials on this subject. This is my ‘build-out’ post. Heh.
Step #9B Pea puffers are carnivores AND territorial. This means that if you wish to add other fish/invertebrates to the mix, you need to do your homework. One specific fish that is generally considered co-habitable is the venerable Otocinclus catfish. These are tiny algae eaters and generally, aren’t bothered by or bother the puffers.
Pea Puffers are lovers of escargot (understatement here), so snails are ON the menu. The exception is the larger types that are ignored. So if you want snails as part of the cleanup crew, pick larger Nerites, mystery snails and adult ramshorns/trumpets. The little ones will get slaughtered. 😀
Last aside. For colder water fish, no heater is necessary. For this
And there you have it. I hope this helps or inspires. There are as many ways to build out an aquarium as there are stars in the sky (I only exaggerate a little here..heh heh), but this is how I do it, and it has been very successful for me.