AP 12 Return chamber drying up

[Snaz]

I have a maxijet 900 as the return pump but I think it is moving too much water as the last two filter chambers are dangerously close to dry. It was working fine until I removed the pump and gave it a good clean, now it runs like Apollo and the last chamber is almost dry. Adding more water to the system just results in the main tank near to overflow. I think the water returns(overflow and middle vents) just can't keep up with the MJ-900

 

Any suggestions? Chamber 1 is filled with LR rubble, chamber 2 has fine particle filter floss but I remove the floss the levels in the last chamber are still very low. Chamber 3 is my heater, Chamber 4 is my MJ-900.

 

The only thing I can think of is chamber 1 is packed too tight at the bottom near the exit but I don't want to disturb the LR rubble. If I move around the LR rubble can it trigger a cycle?

 

I'm worried about running dry. Please help. Thank you.

[Schwanson]

I have a maxijet 900 as the return pump but I think it is moving too much water as the last two filter chambers are dangerously close to dry. It was working fine until I removed the pump and gave it a good clean, now it runs like Apollo and the last chamber is almost dry. Adding more water to the system just results in the main tank near to overflow. I think the water returns(overflow and middle vents) just can't keep up with the MJ-900

 

Any suggestions? Chamber 1 is filled with LR rubble, chamber 2 has fine particle filter floss but I remove the floss the levels in the last chamber are still very low. Chamber 3 is my heater, Chamber 4 is my MJ-900.

 

The only thing I can think of is chamber 1 is packed too tight at the bottom near the exit but I don't want to disturb the LR rubble. If I move around the LR rubble can it trigger a cycle?

 

I'm worried about running dry. Please help. Thank you.

 

I run the exact same setup. The only times I have this issue is when I have a flow restriction in one of the chambers or my water in the tank is getting low. In my case, I only have a few pieces of rubble so that can not be my bottleneck. It is usually the chaetto or the filter floss getting crapped up. Edit: My Chemipure bag clogs up at times as well.

 

If your only potential bottleneck is the rubble and you are concerned w/ what may be there I would:

Turn off the pump.

Rearrange the rubble.

Do a water change siphoning from the back chambers only.

Turn the pump back on.

 

I would also reconsider having rubble back there at all if I was scared of disturbing it. In my case its a few small pieces, I clean it frequently (every 2 weeks), and it is convenient for frag mounting rocks.

[Phixion]

You gotta free up the flow in the chambers. Removing some of the rubble or moving it around shouldn't cause a cycle if you do it carefully. Good luck!

[zook]

Also the MJ900 return pump could be a little fast for the system. I have an AP12 as well and installing a MJ900 causes the water level to go up to the max line, shifts my substrate around, and with a deflector, water actually drips outside the tank; it was too much for my LSP so I downgrade it to an MJ600. I have Karolina Nanos to provide the necessary random flow. I have carbon and purigen in my first chamber and chaeto in the second and third chambers.

[Phixion]

Also the MJ900 return pump could be a little fast for the system. I have an AP12 as well and installing a MJ900 causes the water level to go up to the max line, shifts my substrate around, and with a deflector, water actually drips outside the tank; it was too much for my LSP so I downgrade it to an MJ600. I have Karolina Nanos to provide the necessary random flow. I have carbon and purigen in my first chamber and chaeto in the second and third chambers.

 

Back when I used to have an AP12g, I had an MJ900 and had NO issues with it. I blocked all of the lower intake slats and it allowed for better surface skimming. I also had an ICA chiller in mine with an MJ404 pump in chamber 1, and perhaps with running that my chambers always stayed full, the display itself would drop water level as evaporation occured. Before the ICA, my pump chamber (#4) would lower A LOT, but once topped back off, the display would not raise much if any or overflow...