How to go from gravel to bare bottom without crashing the bio system?

[Sasha]

It's clear from many of the posts on this forum that a bare bottom tank is highly recommended for "growing out" discus. Can someone clarify what the "growing out" stage is? Does this include the 3" juvie stage?

I tried removing about 3 cups of gravel each day for several days during water changes, and I ended up crashing my system - producing a slight ammonia spike and an even bigger nitrite spike. I presume it was because I removed too much of the nitrifying bacteria that was living in the gravel?

I have a HOB filter, and just 4 days ago I added Eheim SubstratePro to the filter box. I also have a pre-filter sponge on the water intake tube. If I remove all the gravel I'm concerned that I won't have enough surface area for the bacteria.

Any advice you can provide would be greatly appreciated. Thanks!

[TURQ64]

1. Grow out refers to discus up to sub adult/ adults...
2. No. most likely, stirred up detritus in the gravel substrate caused the spike
3. Add a sponge filter if you don't already have one...Gravel isn't the best place to grow bacteria in a Discus tank...I have no experince with the Eheim product, so someone else will need to comment...Gary

[Sasha]

Gary - thanks! I don't have sponge filter. If you know of a good one, I'd appreciate any tips or guidance. After I put in the sponge filter, how long should I wait to remove the gravel? And should I do it slowly (a few cups at a time?)

I had no idea that stirred up particles could cause a spike like that. Have any others out there experienced this?

[TURQ64]

ATI sponges in various sizes thru KensFish.com ... Oxygen Plus #4 thru FosterandSmithAquatics.com Glad to be of help...Sponges take a while to get the colony of bacteria going..there are many brands of starter bacteria on the market..Many swear by them, others consider them bunk; your decision...I sometimes use them, but never depend on them

[Darrell Ward]

The size of sponge filter you need depends on the size of your tank. For a tank like a standard 55 gal. up to around a 125 gal., I like to use 2- Hydro Sponge III, one in each corner. The IIIs are versatile, and can be used in different sized tanks without taking up too much space. I would run them one to two weeks to seed them. To remove your gravel, I would move your fish to a temporary tank or bucket containing tank water, drain the tank, remove the gravel, fill, replace fish, and run the sponges along with your HOB for a few weeks.

[Sasha]

Ok - thanks! So you think it will be less stressful on the fish to move them to a bucket vs. removing the gravel over time while they are still in their home tank? I have to be honest, I'm a bit nervous about catching them in a net. They can be really fast and dart around when they want to. :-)

[Bud]

Agree with Darrell.I have an AC110 with prefilter and 2 hydro IV's in my 75!and I waited a solid 3 weeks to let ALL my sponges culture before I removed the sponges my breeder gave me(also a BB tank).I also never let any debri from filters enter tank water when cleaning,seems to really p. them off!Id imagine gravel removal would be same scenerio.You have a BIG net?theyre cheap.JMO

[Keith Perkins]

Ok - thanks! So you think it will be less stressful on the fish to move them to a bucket vs. removing the gravel over time while they are still in their home tank? I have to be honest, I'm a bit nervous about catching them in a net. They can be really fast and dart around when they want to. :-)

YES. Well, at least less stressful on them, you having to catch them is a completely different matter. Pull a little water out of the tank before you go to catch them. Gives you a little comfort zone at the top and less area for you to catch them in.

[gsteve]

Here is what i did. I syphoned 80% of the water out while gravel vaccing to get as much debris out as possible. Then i used a dust pan to scoop out the gravel. I then refilled with treated water and then cleaned the filter after about a hour. Never lost a fish.

[Sasha]

LOL. I guess I have some tolerant juvies. They don't seem to mind much when I vacuum the gravel, despite the floaties that inevitably occur when I do so. I'll get some sponge filters today and will see how my water parameters react over time. Do you think I'll continue to see some small amount of ammonia and nitrite readings until I completely get rid of the gravel? My readings are hovering between 0-0.25 ppm despite my daily water changes.

[gsteve]

I thought i was doing a great job gravel vaccing , i did it 3x a week , thought i was getting it all. After 8 mons all of a sudden all my discus were sick. Didnt think it was the gravel holding junk because i was doing such a good job vaccing. After trying everything drug wise i lost 3 out of four fish. The last guy just sat there hanging in. He looked terrible. I was prepping my tank for my next attempt at discus , it was to be bare bottom. Thats when i removed all the gravel. My last guy came back strong and has now gasined all his size back and then some. BB from now on for me.

[Darrell Ward]

LOL. I guess I have some tolerant juvies. They don't seem to mind much when I vacuum the gravel, despite the floaties that inevitably occur when I do so. I'll get some sponge filters today and will see how my water parameters react over time. Do you think I'll continue to see some small amount of ammonia and nitrite readings until I completely get rid of the gravel? My readings are hovering between 0-0.25 ppm despite my daily water changes.

When the sponge filters cycle, your ammonia levels will likely drop to zero.

[Sasha]

Many thanks to all who have replied :-) By the way, I vac as thoroughly as I can every time I do a change (daily), and sometimes will do a "mini-vac" after a feed. It's a lot of work and I look forward to the day when I can ease up a bit and still have happy, healthy fish.

It does seem odd that my Penguin BioWheel 200 with 2 filter (floss) cartridges and the Eheim biomedia - plus a pre-filter on the water intake tube - wouldn't be enough to handle the bio-load of 4 juvies in a 37 gallon tank.

[Keith Perkins]

Many thanks to all who have replied :-) By the way, I vac as thoroughly as I can every time I do a change (daily), and sometimes will do a "mini-vac" after a feed. It's a lot of work and I look forward to the day when I can ease up a bit and still have happy, healthy fish.

It does seem odd that my Penguin BioWheel 200 with 2 filter (floss) cartridges and the Eheim biomedia - plus a pre-filter on the water intake tube - wouldn't be enough to handle the bio-load of 4 juvies in a 37 gallon tank.

Those filters would handle your fish with ease if the tank was bare bottom, but when you have gravel holding nasties you change the dynamics dramatically. A gravel bottom tank on it's cleanest day is probably still a lot dirtier than a bb one needing a WC.

[Darrell Ward]

Perhaps your tank was merely cycled, and not fully established. It can take months for a tank to mature after initial cycling. It can be a fragile thing until that happens, with the bacteria still growing and expanding.