I will be buying a 5 or 6 foot tank soon and will be using sand instead of gravel. I know that marine tanks use sand so I was wondering how you help stop sand getting sucked up into the filter and damaging the impeller. I'm going to be purchasing a cannister 'Aqua One filter' which is expensive for my budget, so I just want to make sure that it's not damaged by the sand. I was thinking of maybe placing a stocking over the intake filter, but I thought I better ask here seeing most people who have marine fish may be able to help with some information.

Thanks in advance

Oh, I thought I better mention that the new tank is for my Tandanus Catifsh not marine but I need to use sand as they love digging and gravel tends to scrape their skin, leaving their skin open to all sorts of nasty infections, so I need a sand that is soft and rounded

I would just shorten the intake tube so it's not just right above the sand. GIve it a couple inches and you should be fine with it like that.

That is true of most cats, needing sand. Sounds like it will be a neat setup!

Agree....that is what most do when they use a sand as a substrate....Keep it up off the sand just a few inches!!!!

Thanks guys for your replies. Just wondering what type of sand you guys use. Is there a type of sand I should be looking out for, and when I purchase the sand do I give it a rinse like I do the gravel? Not sure about this. Also how do you guys siphing the sand when you clean the tank? Do you siphon the sand as you would gravel?

It depends on how coarse the sand is. My favorite to use is blasting sand, 20 mesh (I get it at a building supply place). I have also used 30 mesh but that is much more fine. I think the 20 would be just fine for a catfish. When you siphon, just hold the tube an inch or so above the sand so it will suck up debris but not the actual sand. You'll play around with it and get the hang of it. Can't wait to see the tank set up!!

In my tank the filter intake is about 4-5 " off the sand bed so that it wont get sucked in. Also when I do a water change I turn off the filter so that when I disturb the sand it doesnt go into the filter either

Thanks again for the feedback and advice. I'm learning quite a bit. So from reading these posts I gather that you dont need to siphon sand, just the debris that settle on top. Is that because nasty things wont grow in between the sand granules like they do gravel?

Your only real concern with sand would be settling where it would get anaerobic pockets. I'm guessing your cat will do a good job himself of keeping the sand stirred. In my last tank with a deep sand bed, I made sure I had plenty of snails to keep the bed stirred.

In your case, with the cat keeping the sand moving, all the nasty particles should be stirred up and sucked up by the filter.

What type of snails did you have in your tannk? Were they apple snails? Also how many cms or inches should of sand do you recommend jsrtist? Thanks again for your advice

I had pest Malaysian trumpet snails in my planted tank. They are excellent sifters without disturbing the plant roots.

Depending on how big your catfish is, I'd say maybe 3-4."