Odd Pump Behaviour, what causes it?

[dopey]

I have a Yasha 37L cube. It did not come with the original pump, and after some research came up with using an SW-4 + PVC pipe.

This has worked for months, but recently i've had an odd behaviour.

Normally when the pump is running, I get a noticeable difference in water level between the back 'sump' area of the AIO and the display area. Like this:


Now I am not a fan of this, as it requires me to keep the pump at a lower setting to not suck air. I've assumed it's due to the force of flow leaving the back area vs the inlets on the other side into the sump not being 'equal'.

Nonetheless, i've learned this is the normal behaviour.

Recently, I have been finding the tank like this:


While it be great if this was OK, I fear it is not.

The actual flow in the main tank is greatly, greatly diminished.

I've learned if I take my tukey blaster and 'blow' water into the inlet from the display tank -> pump, it will 'fix' itself and go back to the normal behaviour.

It will stay this way for an unknown amount of time. Initially it was just after water changes that I needed to do this 'trick'; Now it loses the water level difference on it's own during the day.

I thought I had solved the mystery after cleaning my pumps last week. As for the first time in a while when i plugged the pump in, it created the difference in water levels. However the past day i've had it get into this 'equal' level a few times.

Any ideas?

 

[chipmunkofdoom2]

This setup is a little unique. It's unlike a return pump where flow must go from the pump area to the display. In this setup, flow is free to go anywhere. The SW4 getting dirty can greatly affect flow patterns, which in your case can greatly affect how much water makes it into the display.

Keeping the outlet PVC clean might help, as well as keeping the SW4 clean. This might just be something you have to deal with if you want to keep running this setup. Personally I would re-do the system to use a pump designed to move water through a tube. If not a return pump, maybe something like a Cobalt MJ-400 or Eheim.

 

[dopey]

I was thinking about using a Tunze silence return pump. Place it in the bottom and plumb it into the PVC. This would also remove the concern about sucking air, and not rely on a stream pump to act as a 'return' pump. I've already ordered one, figure worst case i'll use it when doing W/C.

Perhaps it is int the PVC, I haven't tried cleaning that yet.

Agree it's a weird setup, I searched high and low for the stock pump. It simply doesnt' exist anymore I got the tank + protein skimmer + stand for about 75USD, figured it was a good deal. The SW-4 solution was stolen from another person who had done the same setup on their yasha.

 

[dopey]

I thought I'd have to put the pump at the bottom and plumb it..but this seems to work.

 

[DCR]

I don't see any reason why the Tunze arrangement you have will not work as long as air is not being drawn into the inlet of the pump. You could look a the Tunze literature and see if there is anything against mounting it in the vertical, but I think there could actually be advantages with regard to balancing the impeller and venting air out of the suction. I am surprised the SW-4 worked at all, being a powerhead which generally put up very low head.

 

[dopey]

The idea came from another poster who had a friend with the same tank, and had to replace the original pump. I didn't really consider the head pressure since it was just going to push it directly infront. I basically copied their design down to the PVC pipe I was never happy with the difference in water level using the SW-4 caused.

This feels like a much better solution. Only two concerns:
1.) It is a small 'jet' since I have the threaded connector on it. Perhaps it's not needed. If I add fish, perhaps one could swim around the output of the pump and into the back chamber.
2.) If the suction fails, could the pump end up shooting 'up' and out of the tank. Causing quite a mess.

My current plan is to use this on a lower setting, and place an SW-2 pump in the back right corner in a wave mode. This will give me alternating currents and I think overall more even flow around the tank. Right now it feels like the top half of the tank gets a pretty solid flow, but hte bottom corners are a bit of a dead spot.

 

[Forsaken77]

Aqua Medic tank. From what I've found, the original "Nanoprop 5000" pump ranged between 2,000 lph to 5,000 lph, which was controlled on the power transformer.

A review of the tank made it seem that the tank was primarily for inverts and not fish. And said that with the filter setup, you'd be best having "quality live rock" and the "overpowered skimmer" for your main filtration needs because there's no mechanical filtration, which the original pump was designed for.

Have you tried a pump with a prefilter? I agree that a Cobalt pump might work, or any with an available prefilter. Then use a small nano powerhead for flow in the tank. Because the return is not giving you any sort of directional flow and there's no way to adjust that.

The difficult thing is that this tank was built using very specific components to fit in a certain way.

 

[dopey]

Harsh review I hadn't seen that; swear I saw various mixed reef yashas when I googled it.

The purchase itself was impulse. I was returning to the hobby after a 15 year break. I had convinced my SO to go with a Red Sea Nano Max. Oddly we had come up with a 45x45x45 as ideal size, and well that was the nano max. She really wanted a cube. When I got to the store they had this yasha on display(Wasn't on their site), I inquired. They had quit selling it, and offered the display 'as it sat' with stand for less than 1/10th of the Red Sea. Obviously very very different setups and quality, but considering I was just returning I couldn't justify the cost delta.

It was missing the light/return, but had the protein skimmer. After being unable to find the pump, I found that SW-4 setup. As for the light I went with an AI Prime.

The tank is only 5 months old, but not noticed any major limitations yet. The corals I have all seem quite happy, and have had Zoas/Mushrooms/Candy cane all grow additional heads/shrooms. Oddly the only one that I can't seem to get super happy is GSP. Which has led me to the conclusion of low flow in the lower section of the tank. I don't dare put it on the main rock due to it's tendancy to spread.. so i've been investigating a second pump(sw-2) along with this tunze 'true' return pump combo.

 

[Forsaken77]

Harsh review I hadn't seen that; swear I saw various mixed reef yashas when I googled it.

The purchase itself was impulse. I was returning to the hobby after a 15 year break. I had convinced my SO to go with a Red Sea Nano Max. Oddly we had come up with a 45x45x45 as ideal size, and well that was the nano max. She really wanted a cube. When I got to the store they had this yasha on display(Wasn't on their site), I inquired. They had quit selling it, and offered the display 'as it sat' with stand for less than 1/10th of the Red Sea. Obviously very very different setups and quality, but considering I was just returning I couldn't justify the cost delta.

It was missing the light/return, but had the protein skimmer. After being unable to find the pump, I found that SW-4 setup. As for the light I went with an AI Prime.

The tank is only 5 months old, but not noticed any major limitations yet. The corals I have all seem quite happy, and have had Zoas/Mushrooms/Candy cane all grow additional heads/shrooms. Oddly the only one that I can't seem to get super happy is GSP. Which has led me to the conclusion of low flow in the lower section of the tank. I don't dare put it on the main rock due to it's tendancy to spread.. so i've been investigating a second pump(sw-2) along with this tunze 'true' return pump combo.

You don't have to explain to me man . I completely understand. I'm sure you didn't realize how difficult replacement parts would be when you bought it.

Did you try contacting Aqua Medic? They may be able to get you a pump, or at least point you in the direction of a suitable replacement. Just don't tell them you bought it used