Lets talk tall tanks

[four_by_ken]

As some of you know, I have come across a tall tank.  It's 40-42" tall.

What are your experiences with tanks like this?

I have really started to like sand as a substrate, buy I will not be able to stir it up to avoid gas build up.  But, I have never noticed this as a problem in my current tanks.  Should I worry?  Just go with sand, or stick with gravel?

I like a lot of rock my tanks.   I could place rock in the tank, but any rearranging is going to be next to impossible as I will not be able to reach the bottom.  Issues?

As I will have a lot of rock in the tank I will not be able to vacuum much of the gravel, it will be covered in rock.  This is not much of a problem in my current 6' tank as I rearrange every couple months.  I vacuum the entire tank at this time.  I will not be rearranging the new tank very often.

How do I even get things in and out of this tank?  The "grabbers" will work for small stuff, but what about a 10lb rock? 40+lb rock?

To save on buying some rock, what can I use as a base to pile the rock on top of?  I was thinking of building a base of PVC... like a cavern of PVC tunnels.

[Ron]

I have really started to like sand as a substrate, buy I will not be able to stir it up to avoid gas build up.  Buy, I have never noticed this as a problem.  Should I worry?  Just go with sand, it stuck with gravel?

I forget the math and important values at the moment to make a sound scientific statement right now. I think I've posted it in the past on here. In a nutshell, so long as you keep the sand bed depth reasonable (no deep sand beds like you might find in reef tank), you can't produce enough toxic gas within the tank to be of concern.

I like a lot of rock in just tanks.   I could place rock in the tank, not any rearranging is going to be next to impossible as I will not be able yo reach the bottom.  Issues?

"I could place rock in the tank, not any rearranging is going to be next to impossible as I will not be able yo reach the bottom." - I've read that sentence 5 times and am not sure what you're trying to say. It sounds contradictory. If you're unable to reach the bottom, I do think it'll be close to impossible to rearrange.

As I will have a little of rock in the tank I will not be able to vacuum much of the gravel.  This is not much of a problem in my current 6' tank as I rearrange every couple months.  I vacuum the entire tank at this time.  I winter be rearranging the new tank very often.

Water current will be your friend in this situation. FWIW, have you seen any DIY jet systems on any forums yet? Essentially it's a maze of PVC hidden under the substrate with jets that shoot out in strategic locations and are powered by powerheads or larger submersible pumps (including the pump that's running your sump setup if you want to get creative).

How do I even get things in and out of this tank?  The "grabbers" will work for small stuff, but what about a 10lb rock? 40+lb rock?

Drain at least 1/2 the tank, get a ladder ...  . Sounds like fun. I'd be extremely cautious of what you do put in there in terms of fish because they'll be even harder to get out unless they're large enough to be caught by rod and reel. 

To save on buying some rock, what can I use as a base to pile the rock on top of?  I was thinking of building a base of PVC... like a cavern of PVC tunnels.

Not sure how high you're looking to go, but IMO ultimate height depends on tank width to safely build up the base. You could use a marine expoxy to help stack if necessary, but rearranging would be a huge PITA. IMO a styro/cement style background would be best - Steve has some great threads on here already about those!

[Marty]

Python makes extra long gravel vac tubes that you could use to stir up the substrate and siphon waste.  I use one on my 400 gallon and it works fine.

To rearrange rock work, you'll either need to drain a lot of water or drain a little bit and use a scuba mask.

[atmagoulick]

As sone of you know, I have come across a tall tank.  It's 40-42" tall.

That are your experiences with tanks like this?

I have really started to like sand as a substrate, buy I will not be able to stir it up to avoid gas build up.  Buy, I have never noticed this as a problem.  Should I worry?  Just go with sand, it stuck with gravel?

I like a lot of rock in just tanks.   I could place rock in the tank, not any rearranging is going to be next to impossible as I will not be able yo reach the bottom.  Issues?

As I will have a little of rock in the tank I will not be able to vacuum much of the gravel.  This is not much of a problem in my current 6' tank as I rearrange every couple months.  I vacuum the entire tank at this time.  I winter be rearranging the new tank very often.

How do I even get things in and out of this tank?  The "grabbers" will work for small stuff, but what about a 10lb rock? 40+lb rock?

To save on buying some rock, what can I use as a base to pile the rock on top of?  I was thinking of building a base of PVC... like a cavern of PVC tunnels.

I use fine sand form home depot.  It is a good substrate.  Then mix in some laterite with it.  PVC tunnels sound nice.  I would buy the elbows.

[Ogre44]

I've seen people use styrofoam as a base for rockwork.
Cut it to the size you need, silicone some of your substrate to the top and sides, silicone it to the bottom of the tank and you're good to go.
With PVC I'd be worried about trapping detritus in an area of little to no water movement.

If you're worried about cleaning the substrate you could go with gravel and do a reverse flow undergravel filter.
Use a powerhead to push water down the risers and through the plates which in turn pushes detritus out of the substrate and into the water column where your filter can pick it up.
It's used a lot by goldfish keepers to help with all the mess.

[four_by_ken]

I wrote the original post on my cell phone and didnt proof read.  I fixed it up some.

[four_by_ken]

I like the idea of using a couple power heads to create some flow down at the bottom to stop stagnant water.


What is the depth of sand that is ideal to not have to worry about it?

Right now, I think I am just going to reuse the gravel I have.  But, I change my mind often.


Maybe make the PVC tunnels and then "paint" them with the same type of stuff that Steve uses for his backgrounds.  That should make them blend in more and look a little more natural.

[linuxrulesusa]

1" of sand or less is fine IMO.

[Ron]

What is the depth of sand that is ideal to not have to worry about it?

1"-2" and you should be in good shape. 2"-3" and if your substrate shows through the front pane, AKA the stand trim doesn't hide it, you might have darker areas show up (no worries - just not cosmetic to some). 4"-6" would be excessive IMO for a freshwater tank.