9 Fish In a 20 Gallon

kswan · Jul 31, 2018

I had to remove all of the fish from my 90 gallon display due to a velvet outbreak. My quarantine tank is a 20 long with a HOB filter. I had a sponge in the sump for several months that I used to hopefully work as an instant bio filter. I have the following fish in this system:
2x clowns
2x chromis
2x fire fish
royal gramma
diamond goby
flame hawk fish

This seems like too many fish for the 20 gallon. Will it work for the fallow period? If not, what size would be more appropriate?

Humblefish · Jul 31, 2018

Should be fine, but how big is the HOB? Make/model?

declanisadog · Jul 31, 2018

They're are all pretty small fish so while it isn't ideal, you could probably swing it. Frequent water changes, and definitely keep an eye on ammonia.

HotRocks · Jul 31, 2018

kswan said:
I had to remove all of the fish from my 90 gallon display due to a velvet outbreak. My quarantine tank is a 20 long with a HOB filter. I had a sponge in the sump for several months that I used to hopefully work as an instant bio filter. I have the following fish in this system:
2x clowns
2x chromis
2x fire fish
royal gramma
diamond goby
flame hawk fish

This seems like too many fish for the 20 gallon. Will it work for the fallow period? If not, what size would be more appropriate?

Probably a bit small. You may battle ammonia.

I would go with a 40b if you have that option. More room and less stress for the fish, also easier to control ammonia. You can also soak that sponge/or dose with Biospiria or Dr Tims to help boost the biofilter.

ZachH455 · Jul 31, 2018

Flame hawk might go postal in at 20g with that many inhabitants. Wouldn't be an issue in a 40b as someone above suggested.

kswan · Jul 31, 2018

Humblefish said:
Should be fine, but how big is the HOB? Make/model?

It is an Aqueon QuietFlow 20.

kswan · Jul 31, 2018

Thank you all for the quick responses. I'll see about getting a 40b. Would probably need a new filter too. That is a bummer.

HotRocks · Jul 31, 2018

kswan said:
Thank you all for the quick responses. I'll see about getting a 40b. Would probably need a new filter too. That is a bummer.

If you have an ammonia badge and already have them in the 20, you can see how it goes. Just don't overfeed and keep an eye on it, if it becomes an issue then grab a 40b.

kswan · Jul 31, 2018

^^^^That sounds like a good plan. I do have an ammonia badge in the tank.

Humblefish · Jul 31, 2018

kswan said:
It is an Aqueon QuietFlow 20.

I would add a second filter for more flow/oxygen. Even an air driven sponge filter will help. Or a small powerhead pointed towards the surface of the water.

But only feed 1x daily with that small of a biofilter.

kswan · Jul 31, 2018

Humblefish said:
I would add a second filter for more flow/oxygen. Even an air driven sponge filter will help. Or a small powerhead pointed towards the surface of the water.

But only feed 1x daily with that small of a biofilter.

I have a small power head and air stone running currently. I'll keep the feeding to a minimum and watch ammonia. Thanks!

kswan · Jul 31, 2018

I have a few larger pieces of Pukani in my sump. Any issue with putting that in the hospital tank for more bio filter? I understand that I won't be able to put it back in the sump due to copper absorption.

Humblefish · Jul 31, 2018

kswan said:
I have a few larger pieces of Pukani in my sump. Any issue with putting that in the hospital tank for more bio filter? I understand that I won't be able to put it back in the sump due to copper absorption.

The rock will make it more difficult to maintain a stable Cu level.

kswan · Jul 31, 2018

Ok. Thanks

Scotty Buttons · Jul 31, 2018

Petco is doing the dollar per gallon sale right now. You could get a 29 gallon for $29 or you could get a 40B half off which is about $50

kswan · Jul 31, 2018

Funny you mention this. I’m filling a 40b at the moment. Saw the sale and couldn’t help it

.

Scotty Buttons · Jul 31, 2018

Nice! I bought one the other day just because... went into petco for crickets, left with a 40B.

kswan · Aug 2, 2018

I got everyone settled in the 40b and woke up this morning to my diamond goby on the floor

. I knew he may jump and had plans to get a top but hadn't got around to it with all the other qt work. Feel like I can't win...

Averhoeven · Aug 2, 2018

kswan said:
I had to remove all of the fish from my 90 gallon display due to a velvet outbreak. My quarantine tank is a 20 long with a HOB filter. I had a sponge in the sump for several months that I used to hopefully work as an instant bio filter. I have the following fish in this system:
2x clowns
2x chromis
2x fire fish
royal gramma
diamond goby
flame hawk fish

This seems like too many fish for the 20 gallon. Will it work for the fallow period? If not, what size would be more appropriate?

This is about what I've had in my 20L QT for the past few weeks except I've had a small tang. Despite having added Dr Tim's, I feel like I might as well have done TM because I'm doing water changes constantly. Take that for what it's worth.

kswan · Aug 2, 2018

Averhoeven said:
This is about what I've had in my 20L QT for the past few weeks except I've had a small tang. Despite having added Dr Tim's, I feel like I might as well have done TM because I'm doing water changes constantly. Take that for what it's worth.

What is TM?