Avoiding dead spots

[New Boy]

I'm drawing up xmas lists for pressies from my family and I thought it would be a good opportunity to ask for a few bits and pieces towards my 400 litre tank that I plan to get in March.

I want to go with sand (I've currently got gravel in my 190l) substrate but I'm worried about dead spots. I'm planning to put an undergravel plate under the sand and fit it with a powerhead (so that water is blown up through the sand). Will this reduce the risk of dead spots? Am I wasting my time? I plan to have lots of rocks in the tank so this may affect my chances of having dead spots, but I don't want to have to pull them all out once a month......Should I go for gravel instead??

Thanks
Andy

 

[Eelzor]

I see you have some questions on sand. I, in fact have sand, and I think it looks fantastic, but with it, comes quite a bit of responsibility. I don't need the sand, but it is better for the specific creatures I am going to have in the future. The thing with sand is, to stop dead spots from arriving, or to stop nasty bacteria from forming under the packed sand, a few things can be done.

1. Move your finger though the sand about once a week. Lightly mix it, but don't stir it up. It's tempting, but don't.

2.You could also buy quite a few eels or kuhlli loaches. These guys mix the sand around sometimes and do help a little, however you will need quite a few kuhllis as they are quite small also depending on your tank size, and it also depends on what other tankmates are in your tank. (May confuse them as a snack!)

If you have any more questions on the sand feel free to ask.

P.S I find the under gravel filter totally useless. Don't go with it.

......Should I go for gravel instead??

That is completely your choice. If you are willing to take the responsibility for taking care of sand FWIW, go for it!

 

[New Boy]

Will I be able to drag my finger through the sand when i am planning to put lots of rocks in it? That's why i was thinking about the undergravel plate with a blow bit on it to force oxygenated water through the sand and avoid dead spots.

 

[pebbles]

not absolutely sure about this but i don't think you can use an undergravel filter with sand.i am sure others will help out here .... pebbles

 

[CFC]

Sounds like a recipe for disaster, by reversing the flow through a UGF the sand will contantly be blowing around the tank.
Sand requires a little more maintainance than gravel as debries sit on top of it and have to be removed by syphon weekly, you will need to pick up rocks and other objects in the tank when you hoover so just give the sand a little stir when you move them. Alternatively like eelzor suggested add some spiney eels to the tank, they will turn the sand over constantly but your plants will have to go in pots to stop the eels from uprooting them.

 

[New Boy]

Would reversing the flow on a UGF with gravel be of any use? i prefer the look of sand but i'll go with whatever is better for the fish with all of those rocks in there.

Thanks for advice so far

 

[CFC]

IMO UGFs are a waste of time, these days internal and external canister type filters are cheap to buy and do a far better job.
UGFs limit you by not allowing you to have live plants and the whole tank has to stripped down once a year to clean under the plate.

 

[New Boy]

CFC, I'm not suggesting using the ugf as a filter (I'll be using an eheim pro II and a fluval 304 for that) but I read on another forum that you can set up an undergravel plate attached to a powerhead that would blow water down through the plate and up through the gravel and therefore force oxygenated water through the gravel to help avoid dead spots. This was on a mbuna website so was probably by people with lots of rocks in the tank who are at high risk of dead spots. Have you heard of this or other techniques to reduce the risk of dead spots? I just don't want to have to pull all the rocks out monthly (1 'cos it's a major job and 2 'cos it unsettles the fish)

Cheers

 

[joshua]

i've seen my cousin's cory dig up some sand occasionally... not sure if all do that. =) but guess u gonna get big fish who are gonna be aggressive to those cuuuuuttteee cories

 

[CFC]

Ive heard of it but cant see any benefit from it, the end result is the same with lots of sludge and muck trapped beneath the plate The easiest way to avoid deadspots is to only have the substrate about 1" deep so that the fish will stir it up a little in their everyday movements, not a good idea if you have plants but fine in a fish only aquarium.

 

[Lateral Line]

You can have dead spots under large stones with gravel as well.

The sand will fall through the holes/slots in the ugf plate and will clog it. This will happen first furthest from the powerhead, and advance towards it. Your dead spots, if any, will be forming now anyway away from the powerhead. Eventually, all of the flow from the powerhead will be blowing the sand up in a few square inches around the bottom of the delivery tube. I'd forget the ugf.

Use a sand that doesn't compact too much, I always use swimming pool filter sand, and agitate it a little with a chop stick or similar when doing some maintenance. Stuff like silver sand and building sand packs down hard and requires a lot more "gardening".

Another approach is to use undertank/under sand heaters to promote a little circulation by convection. I have tried both Ultratherm pads and Dennerle cables. The cables, in theory, work better - but I didn't find any real difference.

The danger of "dead spots" is overstated.

 

[Eelzor]

With my sand, I have to basically move the rocks and swish the sand lightly under them, then simply put them back down. I have a huge ornament that takes up about 1 quarter of the tank. I have to lift it, then just mix the sand under there as it is a dangerous spot for evil bacteria to grow . I actually find sand easier in some ways because dirt doesn't get under it, so all you have to do is vacuum the top of the sand and lightly mix it once a week. If you are not dedicated enough to do this, then you are not very dedicated to scenery. More questions, just ask away.