Hmm, I always vac my sand and maintain a bed about the same depth. It no doubt gets some particulate in the water but it clears up very well in an hour or 2. I have done this with both my sumpless and sumped/skimmered tank.
The thought behind vacuuming or not does have to do with depth as you run the risk of exposing anerobic bacteria in the bottom but even some that run shallow beds never touch them with the thought being they will remove good things as well as the nasties.
The reason I always vac my bed is because I started that way with my sumpless/skimmerless tank. I felt that by not running a skimmer I needed to do all I could to keep the tank clean and I just have never stopped this process. I have never had an issue like yours so based on my experience I would say vacuuming is not your issue.
I do think there is a right and wrong way to vac though. Stirring it up and just siphoning what you can from the water doesn't work nearly as well as a more controlled siphon. I find it best to work a particular area by crimping the hose to reduce the amount of sand removed and just removing the lighter detritus. I basically siphon a small area full blast and then crimp the hose to let the sand fall back down and then go full blast again just above the sand that falls out. I also find that have a larger siphon works better than the narrow ones. Not trying to tell you how to do things and maybe none of taht made sense but this is what I find works best after 2 years of weekly water changes :thud:
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The thought behind vacuuming or not does have to do with depth as you run the risk of exposing anerobic bacteria in the bottom but even some that run shallow beds never touch them with the thought being they will remove good things as well as the nasties.
The reason I always vac my bed is because I started that way with my sumpless/skimmerless tank. I felt that by not running a skimmer I needed to do all I could to keep the tank clean and I just have never stopped this process. I have never had an issue like yours so based on my experience I would say vacuuming is not your issue.
I do think there is a right and wrong way to vac though. Stirring it up and just siphoning what you can from the water doesn't work nearly as well as a more controlled siphon. I find it best to work a particular area by crimping the hose to reduce the amount of sand removed and just removing the lighter detritus. I basically siphon a small area full blast and then crimp the hose to let the sand fall back down and then go full blast again just above the sand that falls out. I also find that have a larger siphon works better than the narrow ones. Not trying to tell you how to do things and maybe none of taht made sense but this is what I find works best after 2 years of weekly water changes :thud:
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