higher pH, more calcium (more is a relative term)
if the shell starts turning white, raise your pH
if you want snails, they'll eat excess food, and their population will reach homeostasis as regular feedings (for your fish) excess food will only support X snail population
if you don't want snails, ... i could laugh, but that's not fair
for small fish to deal with snails:
dwarf puffer fish (about 1")
zebra loach (about 4")
-there are some larger fish that will deal with them too (i try to focus more on smaller fish)
you could also get assassin snails
... sure go from one snail problem to another ...
not really, ... assassin snails while they are snails, they eat other snails (among other things) and reproduce very slowly (like years before it looks like an excessive population)
you could get spixie snails (i know even less about)
spixie snails will also display some cannibalistic tendencies (for keeping their own population in check)
i would never recommend turtles for snail control as they're beyond messy & totally indiscriminate in what they eat/destroy
i have not come across anything else that is reported to manage snails
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otherwise stick with regular feedings, don't overfeed, and your snails will keep excess food from going to waste
i have some smaller containers that i totally ignore (not fish tanks) with some snails in them, the snails do fine, i top up water, the snails continue to do their thing, pH is rather high (i'm sure around 8 - as those containers have greenwater (and dark greenwater) can't test reliably as the water is colored to start with, ... or at least i haven't tried to test)
again for snail health, ... just watch their shell, if it starts turning white, the water is too acidic
if you don't want snails, make it more acidic, older shell is fine, but if it starts dissolving through newer shell (closer to the body) the snails won't be able to handle this and will die as well. ... not good as this will foul up the water unless you are paying close attention and removing any and all snails you see ... so those that do die and you have missed for whatever reason don't foul up your water too badly.
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many people freak about having snails, (so all the extra info on getting rid of them.
but they are good, if you have malaysian trumpet snails (assassin snails too) these can help turn over the substrate, which is good for substrate health. they also help eat excess food so it doesn't rot & go to waste, ... they're an eye-sore because people don't want them, ... if people would change their mind there's all kinds of snails out there, some are boring, some are rather fascinating to look at, ...
and don't think snails are slow, as i'm sure you've noticed if you see one on the side and can't find it again in the few minutes it took to get a cup of coffee.
I have had 2 plants in my fish tank for about month and half (with the heater on) , I notice that the glass was bit grumpy today and I was going to give a quick clean and I notice there 5 tiny snail in my tank
