After my marine aquarium cycles, do I need to perform a 100% water change?
The vast majority of the beneficial organisms live in and on the live rock and substrate. With nothing but rock and sand in the tank, it wouldn't really matter if you changed all the water after your tank cycles. However, there isn't any need to do so. Check the nitrate level after you're sure the tank has cycled, and base the percentage of your water change on your test result.
Before you distrurb/remove your sand, can you siphon off the tank water into several clean buckets and save it? You'll likely want to remove the water that gets dirty when you remove the sand, but saving some of the water pre-removal could avoid a 100% water change, which could be hard on the fish and snail.
I'm sorry you don't like the sand though. Did you rinse it really well before putting it in the tank?
What kind of sand do you have and how deep is it? You shouldn't need to stick your siphon into it when vacuuming as all the debris/detritus sits right on top. Just swirl your siphon a couple of inches above the substrate and everything just gets sucked right up. You could stir it once in a while but that shouldn't cause any odors.
I have sand substrate but I don't like it, I don't even know why I got it in the first place. The things I hate about it are it makes the water smells, every time I moved something in the tank the sand would come up too and the water would get little cloudy, its super hard to clean using vacuum cuz I would be sucking the sand up too and its really dirty to dealt with. So basically, I want to switch substrate to something like marble glass, rock shape like.. But the problem is if I'm gonna do that then I'll have to do a 100% water change cuz I need to remove the sand and all. I have a betta and a nerite in the tank right now. I just want to know if its safe to perform such water change.
Yes it is safe to do it once in awhile. But I would try to solve the problem another way, First.
Do you have carbon in your filter? This will give your water a more sparkling appearance. It acts as a polish. So that may help. Also using filter floss will help get all those tiny particles out of your water.
Are you sure it isn't the film on the inside of your glass? It can make the water appear as if it has a dusty quality.
If you are going to do a 100% water change I would probably get some bottled bacteria. That way you can add a capful to the filter. It isn't absolutely necessary, and is completely optional, but it won't hurt anything. I usually add a capful of Stability for any water changes over 60%. But I am paranoid about losing my cycle. Lol
I do have carbon in my filter!
And omg what's filter floss? I need some ASAP!
Yeah it's those little particles in my precious water that drive me MAD!
I want it to be pristine like it was when it was first filled.
If your water parameters are stable, ph within .4 and temperature within 2 degrees it is great for fish ( I would do 90% until the fish lay on their sides and circle)- there are no downsides. I have done this frequently in my years of raising discus, it may temporarily stress fish but the benefits of clean healthy water are ten-fold. Your fish will not die or succumb to illness due to these large water changes in either the short-term or the long-term if you are doing them correctly.
Good question, that wouldn't be the case for all fish, my fish are between 7" and 5.5", when I do a 90% water change, they will lie on their sides because they are deep bodied, your fish may not need to do this if they are small with a 90% change.What does it mean if the fish lay on their sides & circle?
I don't agree that it's safe. You have to do something with your stock and that "something" entails risks. Fish that are dropped, stressed or shocked by the transfer. I feel that putting your stock through that kind of stress just so you can have less particles in your water is a bad trade off. However it's your tank and you can do what you like.. .just one opinion. Good luck either way.
The reason I asked the question is because I didn't know the answer. I'm still learning. If it's not safe, I'm not gonna do it.
Someone mentioned filter floss so I'll try that.
Oh and you should be replacing your carbon once a month. So if it has been longer than that, it may be time for new carbon.