More Tank Chem Questions

[zurikitty13]

This is going to seem extreme, but I would like to have an aquarium that I can maintain below 50 ppm of dissolved solids in the water. pH isn't too big of an issue for me, but the closer to neutral the better. It definitely has to be above 6, preferably above 6.5, with 6.8 being the sweet spot. Right now, I have a 20 gallon long tank that I change using only distilled water. I have peat moss in my filter and oyster chick grit to add some KH. My TDS meter reads 147 ppm right now, and my tank has stayed at this level pretty consistently. It's only went up 10 ppm over the course of a month or two (the peat moss is great!). I have a mangrove root and malaysian driftwood in the tank, with some little amazonian frogbit plants floating at the top and I let a lot of algae grow in my aquarium. But only certain kinds. I've let the fuzzy algae grow on the wood, I heard they were actually beneficial, and I get rid of the green-film algae, but not the brown. Not that there's much brown algae. Anyways, I've got the tank decently stocked, 7 nano cories, 3 kuhli loaches, 3 albinos, 2 trilineatus, and one peppered. I'm working on getting the tris and peppered more of their species, but also don't want too high of a bioload, so I'm still planning that out. Now, I know this will be difficult, but I'm up for a challenge, and I would like to add some delicate plants to my tank that require 50 ppm or below water, aka the waterwheel plant. I'm going to get a tropical version, so no need to worry about dormancy! Oh, and I also need the pH to be decently buffered, can't have it swinging around too much, so the majority of the ppm will probably be calcium carbonate I assume.

On one hand, I'd like to go for a heavily planted tank. That'd be a great way to take excess nutrients out of the water, keep the pH low. On the other hand, if I'm not careful with the calcium, the plants could start taking out the buffer and make my pH go crazy. Also, the plant I'm looking to keep is out-competed fairly easily, especially by algae, so I guess I'm going to get rid of my algae by adding some snails, adding some otos, or just scraping it off. I'm looking to have stained, peat-mossy water, so I was thinking of getting Indian Almond Leaves and some oak leaves from my backyard when the season is right. I hear they add helpful properties to the water, for the plant and fish, and waterwheels like tannins and humic acids.

I'd also like to hear ways of maximizing CO2 in the water without artificially adding any, as this plant likes as much as it can get. Here's my thought process: if I make the water great for bacteria, they'll produce more CO2. So, bacteria like neutral water and oxygen. Adding some other plants seems like a good way to do achieve this. For the plants, I plan to get some T-5 bulbs, one a full spectrum and the other a cool white from lowe's.

The most straightforward way to lower ppm is obviously dilute the water. But constantly changing the tank water won't do, so I need to figure out a stable system. I know that this plant will do well with other plants, actually it probably needs to be kept with other plants, so the suggestions I've seen that I'm interested in are duckweed and utricularia, another carnivorous, aquatic plant. I'm planning on just using my frogbit in place of duckweed, though, unless some great need for using that specific species comes to my attention. So, I need to pick some submerged plants that will keep the ppm low, but not take them out too quickly and out compete the waterwheels. So, something of medium-slow growth, I assume? They also won't get as much light due to the floating plants, so they'll have to be able to accept low light conditions.

Right now, I'm eyeing potamogeton gayi, staurogyne repens sp porto velho, and vesicularia dubyana as good submerged plants. I don't want nutrients removed from the water too quickly, so as not to out-compete my waterwheel, but also enough so that the ppm stays down. I also really like all of those plants, and I'd like to stick with south american plants. I'm aiming for a heavily-planted tank, so I'm going to fill up on these and eventually add some more cories and a centromochlus. I'll make sure the christmas moss gets a little more light than the other two, and having fish in the tank should keep the co2 level good enough I think.

Oh, and can anyone recommend fish foods/feeding methods that would reduce the amount that decomposes and wastes in the water? Right now, I use tiny NLS pellets that sink to the bottom. I'm terrible when it comes to feeding my fish; can never tell if I'm over or under doing it.

Here are some helpful links that I've been using as guides on what I'll need to do:
http://www.carnivorousplants.org/cpn/sa ... 3Aldro.htm
http://www.plantsrescue.com/tag/waterwheel-plant/

From my understanding, my cories/loaches should be able to adapt to very soft water, as water quality is more important to them than water parameters, but if there's an issue here, let me know. Worst comes to worst, I have an unoccupied 10 gallon that I could use instead without any fish, but I'd really like to try raising this plant in my 20 gallon long with my fish first. And no, there's no danger of the plants eating my fish; their traps are way too small.

[dw1305]

Hi all,

but I would like to have an aquarium that I can maintain below 50 ppm of dissolved solids in the water. pH isn't too big of an issue for me, but the closer to neutral the better. It definitely has to be above 6, preferably above 6.5, with 6.8 being the sweet spot.........On the other hand, if I'm not careful with the calcium, the plants could start taking out the buffer and make my pH go crazy...Oh, and I also need the pH to be decently buffered, can't have it swinging around too much, so the majority of the ppm will probably be calcium carbonate I assume.

You can't have a stable neutral pH in very low conductivity water, pH is a ratio, and the nearer you get to H2O the less stable it becomes. Any small change in the in the amount of acids "proton donors" and bases "proton acceptors" is reflected in a large change in pH, it isn't a buffered system.

Fish that live in vegetated soft water experience large swings in pH during every diurnal cycle as the amount of dissolved CO2 (a proton donor) and oxygen (a proton acceptor) change. You can add a phosphate buffer (Na2HPO4/NaH2PO4) to retain a pH level, but this is pointless and raises the conductivity.

If you have highly carbonate buffered hard water (like the sea or Lake Tanganyika) conversely you need a large change in chemistry to alter the pH from ~pH8.

I've run out of time now, but I'll post some more on the plant bit of your post when I'm back from field work.

cheers Darrel

[zurikitty13]

Yeah, that's what I thought, which is why this conflicting info I've been reading is kinda weird. Low ppm, but stable pH? Those don't go hand and hand. I'm thinking, the pH can't be as important as the ppm. I've read it does best from pHs 6.8-7.4. So, I'm not sure. Maybe they're referring to the amount of nutrients that are actually available? I forget the term, but some nutrients are more readily absorbable than others. I'm just thinking out loud, though. I think if there's lack of nutrients besides calcium, that it should be okay. If there are plants readily absorbing the majority of the nutrients before the waterwheel can, then it should be alright. Which is why it's always recommended to keep it with other plants.