changing gravel

[wolvo23]

Hi everyone, I have a 6x2x2 tank full with fish and i want to change the gravel and add sand instead can i do this while its full up and running? Input appreciated thanks.

[ant265]

Might be a good idea to move fish temporarily and lower water level to at least half way IMO.

[fongyfong]

Hi everyone, I have a 6x2x2 tank full with fish and i want to change the gravel and add sand instead can i do this while its full up and running? Input appreciated thanks.

I wouldnt, prob kill your fish and it would be easier if you took out the fish and all water and then put the sand in and restart

[wolvo23]

ok will do thanks for the advice

[Josh]

I cant see how it would kill your fish. They might not like it.

As long as the sand is cleaned properly and added carefully. Do the change over on a day when you are doing a water change, remove the gravel, then half the water, add the sand then refill. The tank will be cloudy for a while.

Josh

[japes]

I've changed the type of sand I've used without an issues. I drained half the tank, removed as much sand as I could with a dustpan into buckets, and then washed and added the new stuff bucket by bucket. The main concern is that you need to lower buckets into the tank, which is dangerous when the tanks all clouded up after a bucket or two, because you have a chance of crushing your fish if you slip up, or making them freak out into decor.

Using a PVC pipe right down to the base of the tank and a funnel of some kind could make it a lot neater and less dangerous towards your fish, or if your tank is incredibly long, hearding all the fish down to one end might minimise the risk.

Remember that removing your substrate will take a decent chunk of your bio-bacteria with it, so feed lightly for the next week, or you can do what I did and use a little Seachem Stability; I had 1/4 bottle left over which was a perfect boost.

[fongyfong]

I cant see how it would kill your fish. They might not like it.

As long as the sand is cleaned properly and added carefully. Do the change over on a day when you are doing a water change, remove the gravel, then half the water, add the sand then refill. The tank will be cloudy for a while.

Josh

cos of all the cloudiness and water movement will prob build up stress and plus the possiblity of accidently burying your fish in the sand when your pouring the new sand in, i think its more safter just to empty everything out and start over and easier too.

It would be easier to take out the gravel with no water in it and then vacuum the hard to get places out.

[japes]

cos of all the cloudiness and water movement will prob build up stress

Depends what type of fish, my Eartheaters absolutely love the cloudiness of filter cleans.

[Josh]

I doubt it would be easier to empty the whole tank and start again. I also doubt you would bury a fish, they arent that dumb.

If you have removed all the substrate then I am guessing you would have to remove all decor from the tank first.

If you are worried about crushing fish then remove them to large buckets with airstones. you could even leave the fish in the buckets until the water clears some if you had too

[fongyfong]

I doubt it would be easier to empty the whole tank and start again. I also doubt you would bury a fish, they arent that dumb.

If you have removed all the substrate then I am guessing you would have to remove all decor from the tank first.

If you are worried about crushing fish then remove them to large buckets with airstones. you could even leave the fish in the buckets until the water clears some if you had too

Yeah guess you could move them into buckets and leave the gravel in there, but if you were to try and take out the gravel with water in there it make it harder as some of the pieces of the old gravel would be hard to take out, while with no water in it you could vacuum it out

[pjmowens]

If you are worried about crushing fish then remove them to large buckets with airstones. you could even leave the fish in the buckets until the water clears some if you had too

Yeah guess you could move them into buckets and leave the gravel in there, but if you were to try and take out the gravel with water in there it make it harder as some of the pieces of the old gravel would be hard to take out, while with no water in it you could vacuum it out

the easiest and cleanest way would be to siphon the gravel out. you may go through a little water but just makes sure that you have enough aged water on standby.

[CThompson]

As pjmowens says, siphon the gravel out - what's the problem with that? I've done it many times over the years.

Keep an eye on how much water comes out and don't take too much - take it out over two weeks with the water change water if that helps.

It's then a simple matter of making sure the replacement media is clean before you put it in. Do a good job and the water will stay clean. You don't do a good job and the water will be dirty.

The only fish that will get buried must already be dead - any normal healthy fish with the substrate put in with care will have NO problems.

[Rod54]

I agree with CThompson

I think it would be a very Good idea to syphon out gravel gradually....over 2 weeks?

Not all bacteria is in the filter......there is a Good chance that the substrate will support a high proportion of the nitrifying bacteria....if you remove it gradually it gives time for New bacteria to replace that removed

I'd be concerned replacing all the substrate in a resonable stocked tank in a couple of hours for this reason

[CThompson]

I wouldn't be the least concerned for bacteria reasons. True, gravel has a surface so it hosts bacteria, but the further you go into the substrate, the less O2 = less bacteria. The bulk of the bacteria will be in the biomedia which is why you can start a brand new tank up with an established filter and not expect the tank to cycle (assuming you don’t overload the tank).

Different matter again if you don't have a proper supply of biological media (which may mean the bulk of the bacteria don't reside here). In this case Rod54 raises a very valid point , and in fact a week is not long enough for bacteria to recolonise the new substrate.

The only reason I suggested siphoning the gravel out over two weeks was in case too much water was taken out (dependant on amount of gravel and size (ID) of siphon hose) for a water change (this will also be dependant on whether the hobbyist keeps pre prepared water change water-and how much).

[D6C1]

When I changed my gravel, from crushed coral to black gravel in my 6x2x2 (approx 60kgs worth), I did it in one go.

Take ALL gravel out, put new gravel in.

No issues.

[Nazim]

I have done this before and as long as the new gravel is thoroughly washed and placed gently into the tank, it should not be a problem to leave fish in. As someone else mentioned, the fish aren't dumb and they instinctively know to get out of the way of gravel raining on them.

[teenbies]

I've just done it... changed gravel to sand... I didn't remove the fish, and had no dramas (althought the pleco looked a lil annoyed ) (I hope I read your post right about )

I found that by using 1 20kg bag of Amgrown Kids Play Sand, and washing it in 5ths was the best approach as far as cleaning the sand! Rinse it out until you can see the sand CLEARLY through the water... it took me about 5-6 times of rinsing/swishing...

before

after