Sump - sponge filter

[Eti]

Hi guys,

I have a 65G tank + 30G sump. I do 50% wc everyday with aged water (45G), and the juvies are growing well.

My question is:

My fishes are always active and doing good (begging for food!) when I have the sump on.
But when I run the tank without the sump and only sponge filters (Hydro V) to make wc even faster/easier + better quality control, their behavior is changing drastically: hiding and not eating (despite of 0ammonia 0 nitrate 0 nitrites)

The sponge are now back in the sump with more medias and their behavior is back to normal.
Do you know what could sparkle this drastic change?

Thank you for your help!

[DJW]

I'm having a hard time understanding what it means to not have the sump on. Do you just turn it off, or did you shut it down for a long time and then start it over with a new cycle?

[Eti]

I meant I shut it down for a long time, emptied it and just placed sponge filter in the tank

[Filip]

Common sense makes me think that you had more water and much better filtration with the Sump and your fish loved it.
Now with only sponge filter you have much less nitro bacteria and thus lower water quality .
BTW i dont belive that you could have constant 0 nitrate in a growout discus tank .
This is just my 2 cents.

[Lilly]

95 gallons of water will definitely dilute nitrates more than 65 gallons will. Also the water will have more oxygen . Was the tank cycled before you introduced the babies? Zero nitrates is a sign that the tank is not cycled. What are you using to test your water with?

[Jack L]

just keep sump going if they do better

and you might want to get some new test kits if they are old...0 nitrate seems unlikely

[rickztahone]

I have 2 hydro V sponges in my sump. Good for bacteria colony and to have an insta cycle colony on hand. I noticed that when I put the sponge filters in the tank, the discus went to hide behind it almost immediately. I threw both in the sump and they were all in front of the tank begging for food.

[Eti]

Interesting Rickzathone. Mine were doing exactly the same.

[farebox]

I turn my sump/return water pump off for feedings, but also have an ATI Hydro Sponge Pro Filter #3 in the 125G tank running to keep things going while sump filter is off. Never noticed any difference in behavior. Also while the water pump may be off, my K1 moving bed filter section and Purigen reactor are still running. I moved the heater from the sump to the main tank just to keep the water temp steady while the sump are off for feedings 2 x daily for approx. 45 mins.