water changes

1. What filtration method are you using
2. How much livestock does your tank support
Normal going rate is 10% per week.
If you have a sump then you can afford more bio waste because you have more surface area for biological filtration. Does more stock could be kept depending on what you keep and their environmental needs. (space etc.)
 
Tank Specs

37 gallon
Aquaclear 110 filter
Seaclone 100 Skimmer with Pump
Aquaclear 200 watt heater
45 LB LR
25 LB LS
jbj 1-65w 10,000k; 1-65w blue actnic

Percula Clown
Lawnmower blenny
Cleaner shrimp
5 turbo snail
5 margarita snails
10 red hermits
5 blue hermits
emerald crab

Yellow Polyp
 
4 gals per week should do the trick.
How is your evapuration rate? if you top up often it also helps as long as your parameters stay stable. but dont mistake topping up with a water change. id still stick to atleast 3.5 to 4 gals per week:thm:
 
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