this is one of the few tricks i use from time to time. ill be posting threads on them, detailing some of the odd things i have figured out over the years. some of them might come in handy. this one is a way to get rid of pests in a tank without using harsh chemicals.
sometimes, our tanks can become infected with little critters we might not want, like planaria, pest snails, or scuds. if we are running a planted tank, they can quickly overrun the tank and produce an appearance that is anything but what we want. so, what to do in these situations?
well, one route would be to use harsh chemicals. but, what if we have critters that would die from the residue left over by the harsh chemicals? what then? we could use bleach and then treat the tank with dechlor, but what about the plants? the bleach will kill them. we could use copper, but it could kill shrimp and possibly crayfish after the treatment is done. what do you do when you just want to kill everything without removing the plants?
well, thats where seltzer water comes in. and by seltzer water, i mean regular carbonated water. think about it. we can gas out our tanks out pretty easily if we are injecting CO2 and we let it run too high. in order to do that, however, we have to dissolve the CO2 into the water. think about carbonated water... it already has the CO2 dissolved into it.
if you take a two liter bottle of carbonated water(seltzer water or club soda) you can spike the CO2 levels in the tank instantaneously. this would be extremely dangerous for fish and inverts, so you would have to remove them. but, its just as dangerous to the pest critters as it is to the fish and inverts that you actually want to keep. so, this means that you can dump a LOT of CO2 into the water, drop the ph below the chart in an instant, and start starving the little pest critters for oxygen. the plants will be ok as long as you leave on the lights. some might suffer from the low ph, but even if they do, the treatment lasts a very short time. once its done(after a few hours), the CO2 will have completely dissipated and the tank returns back to normal.
im talking about raising the CO2 to well over 600 ppm instantaneously, before all those pest critters even have the slightest hope of being able to adjust. after they die, let the system go back to normal. the critters will be dead, the plants will still be alive, and you can add your fish and shrimp back into the tank.
personally, this is my favorite technique for getting rid of pond snails. the snails simply cannot handle a blast of carbonated water. as soon as i pour it into a tank, every one of them starts racing for the surface, or dies trying to get there. whatever does manage to escape gets scooped up and converted into shrimp/fish food(crushed).
no residue, no harsh chemicals, and it doesn't kill the plants.
whats not to love?
a word of caution... if you dump a whole bottle of seltzer water in your tank, unless its a very large tank, it will likely kill plants and algae. at least, it will kill the leaves of plants that are exposed. it wont kill the roots. so, you could use this to kill algae as well, if you want to go extremely heavy on the dose.
its similar to the idea of using CO2 gas in a plastic bag to treat plants before adding them to a tank. if you collect plants from the wild and want to use them in your tank, you could use this method to shock the critters off of them. just put water in a bucket, drop your plants in, and when you add the seltzer water, the critters will start dropping off. no harsh chemicals needed.
now if i can only find a specific dosage for each kind of pest critter...
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