Starting over... would appreciate equipment advice


Junior Poster
Feb 2, 2009
I have a 90g tank (48"L x 18"W x 24"H) that I need to tear down due a crack in the stand. Since I have to remove everything, now is a good time to rethink my equipment and layout, and hopefully overcome some of the issues I currently have.

Those issues include a slight BGA issue and a larger BBA problem, both of which indicate there may be a water flow problem. I'm currently diffusing CO2 via a CO2 Diffuser 5000 with a Koralia 1 to move the bubbles around, but I doubt that that's really an optimal solution for a tank this size.

Here is a picture of a layout idea I came up with, but wanted to run it by people who actually know what they're doing (i.e. not me) and see if I'm missing anything.

View attachment 848

Equipment used on the filter loop would include:
Equipment used on the CO2 loop would include:
The Eheim 2076 offers an adjustable flow rate, so between that, the flexibility of the U-Tube returns, and the ball valves I would place on each CO2 return line, I would have the ability to control how much water is coming into the tank and where it goes.

Given all of the above, my questions are:

1. What, if anything, should I change about this plan?
2. Do I need any type of prefilter/sponge on the CO2 intake to prevent the pump impeller from getting clogged with detritus?
3. What size UV sterilizer do I want? Do I go with the 36W to match the flow rating on the filter, or does the '200-300gph' rating on the 18W mean the water would spend more time exposed to the UV light(which sounds beneficial)?
4. If I start the tank back up with HC and Anubias using the dry start method, how often should I mist the plants? I've read "often", but what does that actually mean? Once a day, twice a day, every 8 hours, etc.

Thanks in advance for any input!


Lifetime Charter Member
Lifetime Member
Jan 15, 2009
You might move the cannister spray bar over a bit to the left to give more left/right water movement. I would put some sort of prefilter on the CO2 line if only to keep shrimp/fish/snails out of the "chamber of death", but it will keep other leaves and such out as well. For UV, you want longer dwell time. Too much wattage/exposure is better than too little. Think antibiotics. If you don't use enough strength for long enough, those bacteria that survive are more resistant. Same with the UV. If you're going to use it, you want to make sure you have enough for the job or you're just wasting power.