75 gallon rebuild

[Gerryd]

Mag drives are excellent pumps, but I agree with Leftc that it is underpowered for your overflow rating....

It won't hurt anything, but you will not get the flow rates advertised either

I have used mag drives from the 500 model up to the 1800 and 2400 models. Great, quiet, and reliable.

[Gerryd]

I think your mixture of tubing diameters is also hurting you. A 5/8 or 1/2 hose does not flow a lot of water. Even if the smaller flows to bigger, you will always be constrained by the SMALLEST tube.

I think using larger tubing, say 1", and simply using adaptors at the component level, will offer the best alternative. If you had a sump, you can drop a heater in there and eliminate the hydor.

Can you describe the flow? I think I get it but want to be sure.

[feh]

Its all the same size tubing. 22/16 which is pretty much 5/8 ID tubing... in front tank --> filter --> pH probe/ball valve --> reactor --> heater ---> tank. What I don't get is I had decent flow as things were in that configuration. I moved the pH probe to the other filter. I saw visually no reduction in flow on that filter but no real gain by moving it on the other. I'm running dual Eheims. Even with a huge turbo twist 9x on the other filter I get considerably better flow. The reactor is empty. No bioballs to clog things up. I fiddled with things couple days ago but haven't seen any real increase in flow from that filter. I don't hear any noise to indicate air in it or anything. I even drained and reprimed the filter last week just to be sure. I got an increase but still doesn't feel like the flow I used to have. I always rinse the filter media in the old water as I remove the baskets to clean the canister weekly. I clean the prefilter and change the fine filter pad weekly. I change the prefilter once a month. I also checked the impeller to make sure it was still intact when I drained/reprimed the filter last week. Unless something has gotten lodged in the tubing or another component I suspect the pump. I'm going to swap the filters around later before I do a WC and see if I notice any increase in flow from the filter by running it on the other loop. Also its not the best plumbing but

[feh]

This is why I want to move to a wet/dry sump setup... I don't have to worry about all the inline junk killing the flow and its less clutter. Heater, diffuser in the return chamber and if I really want can run the UV on a closed loop. I don't think I really need it just its there if I do.

[Left C]

Have you cleaned the inside of your tubing? A small buildup in it can really slow the flow down. Eheim has a tubing brush for your 16mm tubing.

[feh]

I have a brush and clean the tubing once a month. I had just cleaned it the week before this happened.

[Gerryd]

5/8 tubing is still pretty small and is not going to flow 500 gph I don't care how many or how large the canister is... so if clogged anywhere as LeftC suggests, could be an issue,.

How about the canister lids and where the flex hose connects? Any blockage?

Try running some simple flex from the canisters to the tank and bypass all the components and see what you get.

Then start including each one until performance suffers....

[Left C]

Good.

Have you cleaned the impellers and their little housing too?

[feh]

The are only rated at 277gph each...

[feh]

Good.

Have you cleaned the impellers and their little housing too?

Yep I check that weekly... clean when needed.