(02-26-2017, 07:22 PM)Thor Wrote: As the matter of fact, soil is one of the least used substrate for planted aquariums. More people are using smaller gravel, sand, and other substrate than soil. Just in any online fish aquarium community you can confirm it.
I dunno, in a Fish community, maybe. If you scroll through the planted tank forums and FB groups, it is becoming far and away one of the more preferred subs. If you put it up by itself against all the other subs together, it is the minority. If you were to combine sand and soil together and compare, they win hands down.
Quote:It is simply easier to make a mess in the fish tank with ordinary soil as substrate. Vacuuming is not the only problem. Some bottom feeder fish will dig around too. Sure you can partially solve the problem by having a thick layer of something else on the top of soil, but it is just more troublesome if they get mixed up.
Mess is relative, more a problem to the keeper than the kept. Same with the bottom feeders, like cories. Many like the softer substrate, digging is natural behavior.
Quote:You may get away without vacuuming if you do not have a fully stocked fish tank. The accumulated organic waste will eventually cause old tank syndrome. It is really hard to keep the nitrate down even with a full tank of plants. Trust me on this. I had covered almost every square inch of the tank with plants yet the nitrate still go up as usual. The only way to prevent it is for me to have fewer fish.
I am all but positive that "old tank sydrome" is a completely misunderstood concept. It certainly exists, but what you need to avoid it is a "bioactive" substrate.
As far as nitrates, There are two ways to prevent it. Have a better way to deal with the nitrates, or produce less organic waste (or as you said, "have less fish", lol!) It is not as simple as "have a lot of plants and they will remove nitrates". All plants, terrestrial & aquatic, require three primary macro-nutrients; nitrogen, phosphorus, & potassium (N,P,K). They are used in a ration, it varies from species to species, aquatic to terrestrial to air, etc. That's why, if you go to home depot or a nursery, there are a variety of fertilizers with different NPK formulations. No3 (nitrate) can't just be overdosed on a plant(s) without the other prerequisite nutrients being proportionately available and be expected to just be sucked up. Unless there is enough readily accessible potassium & phosphorus, (plus enough proportional Co2 & light), the plants will not utilize the No3. They simply physically, biologically, can't. They are not actual filters that you can just use as a pad. They are living creatures that utilize nitric compounds along with other nutrients for their own growth and propagation.
As an example, three days ago, my nitrates climbed up over 30ppm. Because I was slacking and not tracking the levels for a few days. I was almost 0 on phosphorus. My tank overall produces a good amount of nitrogen, and far less phosphorus. The plants utilize all the phosphorus, and as much of the nitrates as they can that correspond to their needed ratio. When the phosphorus runs out, they stop utilizing nitrates, because they can't do anything with that by itself. Two days of calculated phosphorus dosing, and the nitrates have righted themselves to below 10ppm. Because I poured quite a bit of P in the tank in the process.
I now have what is an officially heavily stocked tank with fish (and plants for that matter, I have to trim at least twice a week). In my tank, as long as I make sure to keep the P level up to par with the N produced from the fish/food waste, I have negligible nitrates.
What you need to know is, how much nitrogen is in the tank (including ammonia/ammonium), how much phosphorus is in the tank, how much K is in the tank, what the actual level of disolved Co2 is in the tank (even if you are not adding it, it's in there, and calculable), and how much the light you have can enable the plants to utilize all of these variables. If any of these are too low, they limit the amount of all the others that can be processed by the plants.
Saying "Trust me on this. I had covered almost every square inch of the tank with plants yet the nitrate still go up as usual.", is the equivalent of saying "Trust me on this, I put the highest test gasoline in my car and it still wouldn't start" when you have never checked anything else, the spark plugs, fuel injection, battery, alternator, starter, etc. But yet you still blame it on the gas. Very bad science and problem solving.
Quote:Yes, priority plays a role here too. Some people see their aquatic plants more important than fish. So it is only natural they keep the environment more ideal for the plants. If the fish is your priority, nitrate should be as low as possible. Plants will do fine with even trace amount of nitrogen. You do not need to keep nitrate high just to please the plants.
The priority issue is a big deal here, just as your statement above "just in any online fish community", is close to the exact opposite of what you read in any online aquatic plant community. It goes the other way too. So many of the plant guys are very pro glutaraldehyde supplements, like Excel and Co2 Booster, etc. You can certainly come up with a way to (mostly) safely use that stuff with most fish, but most of the fish people won't touch it.
You don't want to keep "high nitrates", you want to produce high enough nitrogen that the plants can utilize everything at their disposal. If you are reading tests for high nitrates, it is not as simple as having too much nitrogen, it is more correctly looked at as a NPK imbalance (which may in fact be too much nitrogen, but without knowing the other two, you are really guessing), &/or an imbalance of those combined with the levels of light and Co2.
