toxic gasses in sand....

I hear this talked about a lot. And it is usually when sand gets pretty deep and undisturbed. Over time toxic gasses build up or something.
I have avoided having my sand get too deep in any of my tanks for that very reason. And I like to disturb it a bit when doing water changes....just to be safe...

But what about when people do multiple levels of sand. Like a big hill of sand on one side and then flat through the rest of the tank. What happens under the big deep hill of sand? Because I have filled my new 75 gallon with Black diamond sand blasting sand and decided to do a nice big hills/slopes on each side. One side is probably 6 inches deep (maybe even more) at the highest point.... Do I need to be worried about having that deep of sand? Would the hill have to be destroyed and disturbed on occasion to keep from having toxic gasses build up under there? Would having plants on those hills help? Would their roots help? (obviously I wouldn't want to destroy the hills on occasion if I have plants there...and I totally intend on putting plants on the hills....)

To sum it up....How do I void issues with really deep hills of sand? Will my deep hills of sand cause huge issues down the road?

 

Ive never had issuse of this. I0plants would help. If your really concernerd about it get some MTS theyll dig through the sand only disturbing the surface. But I have them in all my tanks. Just don't overfeed.

 

MTS! Seriously, the little critters burrow in the sand and they may be pests to most people but they will help to keep things like gas pockets from forming when wastes decompose in the sand.

Another option that won't disturb the sand too much is to use a bamboo skewer to poke into the sand. Only disturbs it slightly but creates a pathway for any trapped gases to escape.

I think that having plants will help because their roots grow and disturb the sand, albeit very slowly

 

I think the key here is to cause enough small disturbances in the sand on a frequent enough basis so that the gases can be released. The problem happens when people let their substrate sit for weeks and months on end without touching it and then when they start rummaging around in the substrate, the pocket of gas is so huge that it released a plume of toxicity that can't readily dissipate as quickly as little tiny bubbles of gas can. To keep from destroying the hill with plants, I'd use a BBQ skewer to poke into the hill as deep as you can before water changes to allow some of the gas to come through, make sure to poke the entire area thoroughly to avoid missing some spots; then after the water change, most of the badness should have been siphoned out. Assuming you do weekly water changes, that should be enough to keep the pockets of gas from becoming too big to be an issue. Hope that helps!

EDIT: Aquaphobia ninja'd me!

 

That's funny because I had a 10 gallon that had gotten overrun with MTS....and I still have no idea how!! LOL I took that tank down a while ago now though. Too bad because I like the idea of maybe having them in the 75 to keep those hills of sand aerated. And I had a nice supply of them right there!

I just get worried about the tank getting overrun with snails. I hate pest snails!

How does one find/purchase MTS?

edit Aquaphobia and Lchi87 I like the idea of getting something long and skinny to shove deep into the sand hill without disturbing it too much. I will probably go that route rather than MTS. I am anxious to plant my tank!! But I feel like I should wait for the new light first! Off topic, but do plants get "hurt" at all by a not fully cycled tank? Or should I go ahead and start planting? Will the plants slow down the cycling process? I feel I am dealing with a mini-cycle and not a full blown cycle since I have a small nitrate reading from day #1 (thanks to the seeded media) but that nitrate needs to get a little higher to take care of the ammonia spike I am getting. I am hoping that the nitrite stage of the cycle will just be skipped over entirely....but we'll see. I only have two fish in there right now....the tank is 75 gallons so maybe I need more than just two fish to get it going more?

 

Buy a plant from a pet store, that's how I always ended up with mine
bizaliz3, no, plants won't be hurt by a cycling tank. In fact, they love all the extra nutrients IME! I can't blame you for choosing the stick over the MTS route. Sticks are easier to get rid of and don't multiply

Unfortunately, the nitrite stage might not be skipped, only time will tell. I used seeded media but overwhelmed it with too many fish in the QT and ended up with a wicked nitrite spike! It was over in a few days though. Just as well, I was doing massive water changes during that time to keep that one under control. But then it was over and it's been smooth sailing every since;D

 

Unfortunately, the nitrite stage might not be skipped, only time will tell. I used seeded media but overwhelmed it with too many fish in the QT and ended up with a wicked nitrite spike! It was over in a few days though. Just as well, I was doing massive water changes during that time to keep that one under control. But then it was over and it's been smooth sailing every since;D

I feel like I have got the opposite problem. Rather than having spikes due to too many fish at once...I am worried that the BB is starving due to NOT ENOUGH fish....I worry that just two small fish in a 75 gallon might not be providing enough food for the BB on my established media? That established media was used on a 20 gallon with the same two fish that are in the 75 now. I did add another cartridge from another one of my other established tanks...But it doesn't seem to have made a difference.

I will be curious to see how the readings come out tonight.

 

Agreed with Aquaphobia on the plants. I've always planted early on, partially to keep the excess nutrients in check and also because it's easier to plant before all those pesky fish get in the way haha.

If you think those two fish aren't enough to sustain your BB, maybe you can try overfeeding slightly? They just need an ammonia source and I feel better about overfeeding a bit than I do about dropping pure ammonia into a tank.

 

If those 2 fish were the only ones in the 20 gallon and you moved all your media with the fish to the 75 then there should be exactly enough waste to feed the bacteria. The only thing that might cause problems is the gph rating on the new filter and whether it's running the full volume of the tank pas the BB at a high enough rate to feed the bacteria in a timely fashion!

 

If those 2 fish were the only ones in the 20 gallon and you moved all your media with the fish to the 75 then there should be exactly enough waste to feed the bacteria. The only thing that might cause problems is the gph rating on the new filter and whether it's running the full volume of the tank pas the BB at a high enough rate to feed the bacteria in a timely fashion!

That is what I thought....but I was starting to wonder if having 55 more gallons of water was diluting it a bit...even though it was the same two fish and the same media.....you know?

As for the GPH on my filters...I have the marineland bio-wheel 350 which is supposedly 350 GPH. And I also put my marineland bio-wheel 150 on there which is supposedly 150 GPH. So I am running 500 GPH which means the tank is getting 6-7X filtration per hour. Would that be "feeding the BB in a timely fashion'?

 

The 6x is just from your 350, do you add the 2 gph ratings together when using multiple filters on the same tank? If so, then your actual turnover is approximately 9x your tank volume per hour and given that the recommended filtration when using HOB filters is 8-10x I think you're safe

However! Is all the cycled media in one of those filters? In that case you may see a spike because one filter on its own won't be pulling all the water through the cycled media often enough to process the ammonia. So yes, there will be a cycle bump.

 

The 6x is just from your 350, do you add the 2 gph ratings together when using multiple filters on the same tank? If so, then your actual turnover is approximately 9x your tank volume per hour and given that the recommended filtration when using HOB filters is 8-10x I think you're safe

I was adding the two together....350 GPH plus 150 GPH for a total of 500GPH. Then I divided 500 by 75 to determine the turnover rate and came up with 6.67 So I thought it was 6-7x per hour then.....

Am I understanding that wrong?

All of the seeded media was in the bigger of the two filters. (The one doing 350 GPH) Another issue I just thought of may be that the 20 gallon also had a sponge filter and I did NOT move the sponge filter to the 75 gallon. So there was a lot of BB on the sponge filter that did not get moved to the new tank....But all the filter cartridges from the 20 were moved over....For a total of 3 cartridges....Also maybe worth mentioning...the 20 gallon was an understocked and overfiltered tank with multiple water changes PER WEEK. So it didn't have a whole lot of nitrates or BB to begin with....

regardless, I am hoping this is just a cycle bump...or a minI cycle, or whatever....and I hope it passes quickly. I don't have the energy to go though a long cycle process right now!! uggh

 

No, I can't seem to operate a calculator: I entered 55 instead of 75

Ah, yes, a lot of BB would have been in the sponge so yes, you will be experiencing a bump

 

I seriouy doubt plantroots prevent anaerobic build up in a thick layer of sand. The roots might even start to rot themselves if oxygen can get at them.
A thin layer, using pfs (cause of grainsize / shape) and mts will help.

 

I seriouy doubt plantroots prevent anaerobic build up in a thick layer of sand. The roots might even start to rot themselves if oxygen can get at them.
A thin layer, using pfs (cause of grainsize / shape) and mts will help.

so...."anaerobic build up" aside....are you saying anything I plant on those hills are in danger of having their roots die off? That concept really bums me out....because I planned to do a staurogyne repens forest on one of the hills!

 

so...."anaerobic build up" aside....are you saying anything I plant on those hills are in danger of having their roots die off? That concept really bums me out....because I planned to do a staurogyne repens forest on one of the hills!

For some plants, yes, this could be an issue. However, I have S. repens planted in sand in my kuhlI tank and they are thriving. I make sure that the sand underneath them is moved around periodically but that's about it.

 

For some plants, yes, this could be an issue. However, I have S. repens planted in sand in my kuhlI tank and they are thriving. I make sure that the sand underneath them is moved around periodically but that's about it.

My current s. repens is in sand that is about 2.5 inches deep. I have never had a problem. The roots have made it all the way down (I can tell because they are right up against the glass in the front of the tank and I can see some of their roots under the sand where it touches the glass, its cool)

now I am just worried about the depth of the sand in the area I want to put them in my new tank :-(

 

My current s. repens is in sand that is about 2.5 inches deep. I have never had a problem. The roots have made it all the way down (I can tell because they are right up against the glass in the front of the tank and I can see some of their roots under the sand where it touches the glass, its cool)

now I am just worried about the depth of the sand in the area I want to put them in my new tank :-(

Unless someone can definitively say that planting your S. Repens on a hill WILL kill them, I see no harm in trying? I figured you're already going to be poking holes in the sand periodically to allow for the release of gases, I'm assuming it will help oxygenate the roots as well. It goes both ways, right?

 

Unless someone can definitively say that planting your S. Repens on a hill WILL kill them, I see no harm in trying? I figured you're already going to be poking holes in the sand periodically to allow for the release of gases, I'm assuming it will help oxygenate the roots as well. It goes both ways, right?

ya, you are probably right. And the roots can grow sideways too....they don't have to go straight down. I assume if the roots were starting to feel suffocated...they would stop growing downward and start branching sideways....

I can't wait to plant my s. repens in this tank!!

 

Plant away. I still think mts would be the way to go. But I like tanks that are as self sustaining as possible. Lets see some pics btw.

 

Plant away. I still think mts would be the way to go. But I like tanks that are as self sustaining as possible. Lets see some pics btw.

I haven't done any aquascaping yet. I've just thrown some decorations that I had laying around. But I like my sand hills on the sides and want to keep them for sure!! It's hard to see them in this picture though. The hill on the right side is deeper...

Here's before I added the bubble wall. You can see it a little better there

 

Hills always add depth to a tank. Looks good.