Right now I don't have fish in my fish tank and I have small size blue gravels for my goldfish tank. Actually last time when I was cleaning my gravles throghly, my water was completly went blue then after sometime it clears as crystal automatically. And as I heard small gravel may not be suitable for goldfish as they pick those up thinking as food and through them out of their mouth, I have noticed it.

I think this gravle also a bed for good bacteria so if I change these gravel or put a layer of big size gravel on top of the existing gravel, I may loose good bacteria.....or what I should do...looking for answer...please...

SandyDoss

Hi SandyDoss,

What I have done in the past when changing gravels was gradually change it out. I would take 1/2 of the tank gravel out after a really good vacuuming and replace that 1/2 with the new gravel. Then after a week or so if my water params are still good I will change out the other 1/2 of it.

There is good bacteria in your filters, on your ornaments, plants, etc... it is normally not just on your gravel. Without knowing what all is in your tank, your filter type, etc... I couldn't say just take 100% out and change it or not.

But in my opinion, it is better safe than sorry.

Always vacuum the heck outta the aquarium before you change your gravel though as to not stir up too much junk into the water.

I hope this helps,

RHankinsJr

I agree, if you want to remove or replace your gravel, do only half or so at a time, with a week between halves. This way, the bacteria in your filter have time to compensate for the loss (if getting rid of gravel outright) or the new gravel has time to become colonized.

However, since there's no fish in the tank, there's no food for the beneficial bacteria... so you need to make sure the cycle doesn't die from lack of food. Is the lack of fish only temporary (they've been relocated for now), or is it a vacant tank? You can leave it vacant for a couple days, but I'd be careful as cycles can react poorly to changing fish stocking conditions (we had dangerous ammonia levels in a cycled tank just from adding an algae eater... he ate the algae, produced extra waste, and the bacteria couldn't keep up for several days)

I have a 29 gallon bowfront glass tank, areo 4 areator with a Topfin 40 filter with bio filter which has one sponge and one with three chamber two for carbon and one chamber for other (aqual or something) I guess for ammonia treatment.

So, as far you guys, I should not just overlay another layer of large size gravel, right?

I had two goldies but I lost them while treating with salt for fluke and I was looking for answer a quite while in my earlier post that what could happend after adding salt, I checked my water with API drops that my PH was around 9 or higher, did not check the high range PH...as I was so sad..Is this situation normal or what should be the precaution if I want to do it again in future...I just used 2 dosage of salt in 12 hour apart...1 tsp per gallon....Now after 50% water change my PH is back to 7.2 and everything else is fine...

Okay, I will change my gravles in two part after checking the water chemistry in-between.

Thanks for your reply...

My personal opinion would be to not stack the larger gravel on top of the smaller.

The deeper the gravel base you have, the more room there is to get poop, food and other things lodged into it. Not to mention the extra cleaning time and hassle that will eventually end up with the large gravel and smaller gravel being just mixed together.

I'd just do it in multiple changes and keep on going.

However, I missed the part that said you are fishless right now. As 'A Penguin' said, you will need to feed your bacteria to keep them alive if you are going to be fishless for more than a couple days.

For more information on keeping the cycle alive you can see the fishless cycle page here at koko's. I will post a link as soon as I find it, i can't seem to find it right now but I know it exists!

Fishless Cycling @ Koko's

There's the fishless cycling link. Very informative and helpful.

What you'll need to do is add drops (25-35, maybe) of ammonia every day to feed the bacteria. The ammonia needs to be plain, unscented, and not sudsing.

Good luck!

Thanks for updating me, I was not aware of this fishless Cycle....